JP6121599B2 - Maintenance liquid - Google Patents

Description

The present invention relates to a maintenance liquid for an inkjet discharge apparatus used for installing a photocurable composition on a base material or a mold in a photoimprint method for transferring the surface shape of a mold to the surface of a substrate.

  The imprint method is a mechanical deformation that is achieved by developing an embossing technique that is well-known in optical disc production, and pressing a mold (generally called a mold, stamper, or template) with an uneven pattern into a resist. This is a technology for precisely transferring fine patterns. Once a mold is manufactured, it is economical because it can be easily and repeatedly formed with microstructures such as nanostructures. In addition, it is a processing technology with few harmful wastes and emissions, and in recent years it has been applied to various fields. Expected.

  The imprint method includes a thermal imprint method using a thermoplastic resin as a material to be processed (for example, see Non-Patent Document 1) and a photo-imprint method using a photocurable composition (for example, see Non-Patent Document 2). The following two techniques have been proposed. In the optical nanoimprint method in which the curable composition for photoimprinting is photocured, it is not necessary to heat the material transferred when the mold is pressed, and imprinting at room temperature becomes possible.

In such an imprint method, the following nanoscale applied technologies have been proposed.
The first technique is a case where a molded shape (pattern) itself has a function and can be applied as various nanotechnology element parts or structural members. Examples include various micro / nano optical elements, high-density recording media, optical films, and structural members in flat panel displays. The second technology is to build a multilayer structure by simultaneous integral molding of microstructure and nanostructure and simple interlayer alignment, and apply this to the production of μ-TAS (Micro-Total Analysis System) and biochips. It is what. The third technique is used for processing a substrate by a method such as etching using the formed pattern as a mask. In this technology, high-precision alignment and high integration enable high-density semiconductor integrated circuit fabrication, liquid crystal display transistor fabrication, and magnetic media for next-generation hard disks called patterned media instead of conventional lithography technology. It can be applied to processing. In recent years, efforts have been made to put the imprint method relating to these applications into practical use, including the aforementioned technologies.

  As an application example of the imprint method, an application example for manufacturing a high-density semiconductor integrated circuit will be described first. 2. Description of the Related Art In recent years, semiconductor integrated circuits have been miniaturized and integrated, and photolithography apparatuses have been improved in accuracy as a pattern transfer technique for realizing the fine processing. However, it has become difficult to satisfy three requirements of fine pattern resolution, apparatus cost, and throughput for further miniaturization requirements. On the other hand, as a technique for forming a fine pattern at a low cost, an imprint lithography technique, particularly nanoimprint lithography (optical nanoimprint method) has been proposed. For example, Patent Document 1 and Patent Document 3 listed below disclose nanoimprint technology in which a silicon wafer is used as a stamper and a fine structure of 25 nm or less is formed by transfer. In this application, it is required that the number of transfer defects is extremely small in order to improve the pattern formability at the level of several tens of nanometers, high etching resistance for functioning as a mask during substrate processing, and yield improvement.

  In next-generation hard disk drives (HDDs), technologies such as discrete track media and bit patterned media have been proposed which are solved by filling tracks between non-magnetic materials and physically and magnetically separating them. An imprint application has been proposed as a method of forming a magnetic or nonmagnetic pattern in the production of these media. Also in this application, a pattern forming property of several tens of nm level and high etching resistance for functioning as a mask during substrate processing are required.

  Also in the manufacture of flat displays such as liquid crystal displays (LCDs) and plasma displays (PDPs), the manufacture of thin film transistors (TFTs) and electrode plates, or Patent Documents 4 and 5 are associated with the trend of larger substrates and higher definition. The application of the optical imprinting method to the transparent protective film material described and the spacer described in Patent Document 5 is also beginning to be studied, and the optical imprinting method has recently attracted attention as an inexpensive lithography that replaces the conventional photolithography method. Has been.

Furthermore, microelectromechanical systems (MEMS), sensor elements, optical components such as diffraction gratings and relief holograms, nanodevices, optical devices, optical films and polarizing elements for the production of flat panel displays, thin film transistors for liquid crystal displays, organic transistors , Color filter, overcoat layer, pillar material, rib material for liquid crystal alignment, microlens array, immunoassay chip, DNA separation chip, microreactor, nanobiodevice, optical waveguide, optical filter, photonic liquid crystal, antireflection structure The imprint method is also useful in permanent film formation applications such as (moth eye).
In the photoimprint method, a photocurable composition is placed on a base material or a mold, irradiated with light with the photocurable composition sandwiched between the base material and the mold, and the photocurable composition is cured. A pattern can be obtained by releasing the mold. Various methods such as a spin coating method have been proposed as a method for placing a photocurable composition on a substrate. Patent Document 6 proposes a method of applying a photocurable composition using an inkjet. This inkjet coating method allows you to specify the position of the resist droplets on the substrate and apply the resist discretely, so the required amount can be placed on the substrate according to the density of the pattern, and the remaining film thickness Can be made uniform.

US Pat. No. 5,772,905 US Pat. No. 5,956,216 US Pat. No. 5,259,926 JP 2005-197699 A Japanese Patent Laying-Open No. 2005-301289 JP 2005-533393 A

S. Chou et al .: Appl. Phys. Lett. Vol. 67, 3114 (1995) M. Colbun et al,: Proc.SPIE, Vol. 3676,379 (1999)

  However, when the inventors of the present application have studied, when a pattern transfer is performed by discharging a photocurable composition onto a substrate or a mold using an inkjet apparatus, a fine pattern, particularly an ultrafine pattern size of 50 nm or less. It was found that the pattern transferability was inferior in the pattern.

  An object of the present invention is to solve the above problems. That is, the problem to be solved by the present invention is to provide a technique for reducing defects in pattern transfer even when an ultrafine pattern is transferred.

  As a result of intensive studies by the inventor under the above problems, it has been found that the maintenance liquid used when cleaning the ink jet apparatus has an influence on the pattern transfer property. Then, from the maintenance liquids of a large number of ink jet devices, it is found that the defect of pattern transfer is greatly improved by adopting one containing a compound having an ester and / or ether functional group, and the present invention is completed. It came to. It is extremely unexpected that the selection of the type of maintenance liquid contributes to pattern transfer defects.

Specifically, it was achieved by the following means.
(1) A photocurable composition containing a polymerizable monomer as a main component is ejected onto a substrate or a mold having a fine pattern using an inkjet apparatus, and the photocurable composition is finely divided into the substrate and the substrate. A maintenance liquid for an inkjet apparatus used in a pattern forming method including light irradiation in a state of being sandwiched between molds having a pattern, wherein the maintenance liquid contains a compound having an ester and / or ether functional group.
(2) The maintenance liquid according to (1), wherein the maintenance liquid contains a polymerizable monomer.
(3) The maintenance liquid according to (1) or (2), wherein the compound having an ester and / or ether functional group is a polymerizable monomer.
(4) The maintenance according to (2) or (3), wherein at least one of the polymerizable monomers contained in the maintenance liquid is in common with at least one of the polymerizable monomers contained in the photocurable composition. liquid.
(5) The maintenance liquid according to any one of (1) to (4), wherein the photocurable composition contains (meth) acrylate.
(6) The maintenance liquid according to any one of (1) to (5), wherein the photocurable composition contains (meth) acrylate having an aromatic group and / or an alicyclic hydrocarbon group.
(7) Any one of (1) to (6), wherein the polymerizable monomer contained in the maintenance liquid contains a (meth) acrylate having an aromatic group and / or an alicyclic hydrocarbon group. Maintenance liquid described in 1.
(8) At least one polymerizable monomer contained in the maintenance liquid and at least one polymerizable monomer contained in the photocurable composition are each an aromatic group and / or an alicyclic hydrocarbon. The maintenance liquid according to any one of (1) to (7), which contains (meth) acrylate having a group.
(9) The maintenance liquid according to any one of (1) to (8), wherein 99% by mass or more of the polymerizable monomer contained in the photocurable composition is (meth) acrylate.
(10) The maintenance liquid according to any one of (1) to (9), wherein the viscosity of the maintenance liquid at 25 ° C. is 50 mPa · s or less.
(11) Any one of (1) to (10), wherein the maintenance liquid includes a compound having both an ester functional group and an ether functional group, or includes both a compound having an ester functional group and a compound having an ether functional group The maintenance liquid according to item 1.
(12) The maintenance liquid according to any one of (1) to (11), wherein the maintenance liquid has a boiling point at 1 atm of 150 ° C. or higher.
(13) The maintenance liquid according to any one of (1) to (12), wherein the maintenance liquid contains 50% by mass or more of a compound having an ester and / or ether functional group.
(14) A method for producing a maintenance liquid according to any one of (1) to (13), wherein the method comprises filtering after blending the components constituting the maintenance liquid. .
(15) A photocurable composition containing a polymerizable monomer as a main component is discharged onto a substrate or a mold having a fine pattern using an ink jet apparatus, and the photocurable composition is finely divided with the substrate. A cleaning method for an ink jet apparatus used in a pattern forming method including light irradiation in a state of being sandwiched between molds having a pattern, wherein the maintenance liquid according to any one of (1) to (13) is used. Cleaning method.

  When the maintenance liquid for the ink jet apparatus of the present invention is used, even if an ultrafine pattern is transferred, there are few pattern transfer defects and a good pattern can be formed.

It is the schematic which shows the structure of the inkjet head periphery flow path used in the example of this application. It is the schematic which shows the washing | cleaning method of the nozzle surface performed in the Example of this application. It is the schematic which shows the state of droplet ejection of the photocurable composition on the silicon wafer performed in the Example of this application. Here, FIG. 3A is a schematic diagram showing the interval at which droplets are ejected onto a silicon wafer, and FIG. 3B is a diagram showing an image of rotating an inkjet head.

  Hereinafter, the contents of the present invention will be described in detail. The description of the constituent elements described below may be made based on typical embodiments of the present invention, but the present invention is not limited to such embodiments. In the present specification, “to” is used to mean that the numerical values described before and after it are included as a lower limit value and an upper limit value.

In the present specification, “(meth) acrylate” represents acrylate and methacrylate, “(meth) acryl” represents acryl and methacryl, and “(meth) acryloyl” represents acryloyl and methacryloyl. In the present specification, “monomer” and “monomer” are synonymous. The monomer in the present invention is distinguished from an oligomer and a polymer and refers to a compound having a weight average molecular weight of 2,000 or less. In the present specification, the polymerizable compound means a compound having a polymerizable functional group, and may be a monomer or a polymer. The polymerizable functional group refers to a group that participates in a polymerization reaction.
The “imprint” referred to in the present invention preferably refers to pattern transfer having a size of 1 nm to 10 mm, and more preferably refers to pattern transfer having a size (nanoimprint) of approximately 10 nm to 100 μm. In the present invention, particularly remarkable effects are exhibited when transferring a pattern size of 100 nm or less, preferably a pattern size of 50 nm or less.
In addition, in the description of the group (atomic group) in this specification, the description which does not describe substitution and non-substitution includes what has a substituent with what does not have a substituent. For example, the “alkyl group” includes not only an alkyl group having no substituent (unsubstituted alkyl group) but also an alkyl group having a substituent (substituted alkyl group).

(Maintenance liquid)
The maintenance liquid of the present invention discharges a photocurable composition containing a polymerizable monomer as a main component onto a substrate or a mold having a fine pattern using an ink jet apparatus, A maintenance liquid for an inkjet apparatus used in a pattern forming method including light irradiation in a state sandwiched between a substrate and a mold having a fine pattern, the maintenance liquid containing a compound having an ester and / or ether functional group It is characterized by.

Compound having an ester and / or ether functional group The compound having an ester and / or ether functional group may or may not have a polymerizable functional group, but has a polymerizable functional group. It is preferable from the viewpoint of compatibility with the photocurable composition.
As the compound having no polymerizable functional group, glycols, glycol monoethers, glycol diethers, glycol monoesters, glycol diesters, and glycol monoether monoesters are preferable.
Specifically, glycols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, dipropylene Glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monobutyl ether, propylene glycol n-propyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monobutyl ether, tripropylene glycol monomethyl ether Glycol monoethers such as tellurium, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, diethylene glycol methyl ethyl ether, tetraethylene glycol dimethyl ether, tetraethylene glycol diethyl ether and other glycol diethers, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate , Ethylene glycol monobutyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether acetate, ethyl Glycol monomethyl ether propionate, ethylene glycol monoethyl ether propionate, ethylene glycol monobutyl ether propionate, diethylene glycol monomethyl ether propionate, diethylene glycol monoethyl ether propionate, diethylene glycol monobutyl ether propionate, propylene glycol monomethyl ether Propionate, dipropylene glycol monomethyl ether propionate, ethylene glycol monomethyl ether butyrate, ethylene glycol monoethyl ether butyrate, ethylene glycol monobutyl ether butyrate, diethylene glycol monomethyl ether butyrate, diethylene glycol monoethyl ether butyrate, di Glycol monoether monoesters such as ethylene glycol monobutyl ether butyrate, propylene glycol monomethyl ether butyrate, dipropylene glycol monomethyl ether butyrate, ethylene glycol diacetate, diethylene glycol diacetate, propylene glycol diacetate, dipropylene glycol diacetate, Ethylene glycol acetate propionate, ethylene glycol acetate butyrate, ethylene glycol propionate butyrate, ethylene glycol dipropionate, ethylene glycol acetate butyrate, diethylene glycol acetate propionate, diethylene glycol acetate butyrate, diethylene glycol propionate butyrate The Tylene glycol dipropionate, diethylene glycol acetate dibutyrate, propylene glycol acetate propionate, propylene glycol acetate butyrate, propylene glycol propionate butyrate, propylene glycol dipropionate, propylene glycol acetate butyrate, dipropylene glycol acetate propionate Glycol diesters such as dinate, dipropylene glycol acetate butyrate, dipropylene glycol propionate butyrate, dipropylene glycol dipropionate, dipropylene glycol acetate dibutyrate, and dioxane, trioxane, furan, tetrahydrofuran, methyltetrahydrofuran , Methylfuran, tetrahydropyra , Furfural, tetrahydropyran-4-carboxylic acid methyl ester, cyclic ether compounds such as tetrahydropyran-4-carboxylic acid ethyl ester, β-butyrolactone, γ-butyrolactone, γ-valerolactone, γ-hexalactone, γ-hepta Lactone, γ-octalactone, γ-nonalactone, γ-decalactone, γ-undecalactone, δ-valerolactone, δ-hexalactone, δ-heptalactone, δ-octalactone, δ-nonalactone, δ-decalactone, δ -Cyclic ester compounds such as undecalactone and ε-caprolactone are also preferred.

Only one type of compound having an ester and / or ether functional group may be included, or two or more types may be included. The compound having an ester and / or ether functional group may have either an ester functional group or an ether functional group, but the maintenance liquid preferably has both an ester functional group and an ether functional group. Moreover, it is mentioned as a preferable form to use together the compound which has an ester functional group, and the compound which has an ether functional group.
The total content of the compounds having an ester and / or ether functional group in the maintenance liquid of the present invention is preferably 50% by mass or more, more preferably 70% by mass or more, and further preferably 90% by mass or more. The upper limit is not particularly defined, but is usually 100% by mass or less.

The maintenance liquid preferably has a polymerizable monomer. By blending the polymerizable monomer, the familiarity with the polymerizable monomer which is the main component of the photocurable composition is improved, the detergency is improved, and the imprintability is further improved. The maintenance liquid of the present invention may contain an ester having a polymerizable group and / or a compound having an ether functional group as the polymerizable monomer, and separately from or in addition to the compound. Further, other polymerizable monomers may be included. In the present invention, the polymerizable monomer contained in the maintenance liquid preferably contains at least an ester having a polymerizable group and / or a compound having an ether functional group.
The type of the polymerizable monomer is not particularly defined, but examples thereof include polymerizable monomers contained in the photocurable composition described later, (meth) acrylate compounds, vinyl ether compounds, epoxy compounds. And oxetane compounds, which are more effective when (meth) acrylate is used. Furthermore, it is preferable that at least one polymerizable monomer contained in the maintenance liquid is in common with at least one polymerizable monomer contained in the photocurable composition. By setting it as such a structure, familiarity with a maintenance liquid and a photocurable composition becomes good, and a cleaning power improves more. In the present invention, it is particularly preferable that 99% by mass or more of the polymerizable monomer contained in the maintenance liquid is (meth) acrylate. When the polymerizable monomer is a compound having an ester and / or ether functional group, it may or may not contain a non-polymerizable compound having an ester and / or ether functional group.

In particular, in the present invention, at least one of the polymerizable monomers contained in the maintenance liquid and at least one of the polymerizable monomers contained in the photocurable composition have similar structures and properties, respectively. It preferably corresponds to a compound included in the compound group. As examples of such a compound group, the following (1) to (6) are exemplified.
In particular, in the present invention, at least one of the polymerizable monomers contained in the maintenance liquid and at least one of the polymerizable monomers contained in the photocurable composition are each included in the following compound group (1). It is preferable that In the present invention, at least one polymerizable monomer contained in the maintenance liquid and at least one polymerizable monomer contained in the photocurable composition each correspond to the following compound group (2). It is also preferable that it is contained in the compound group.
(1) (meth) acrylate group having aromatic group and / or alicyclic hydrocarbon group (2) polymerizable compound group having at least one of fluorine atom and silicon atom

(3) Compound group containing at least two fluorine-containing groups selected from a fluoroalkyl group and a fluoroalkyl ether group, and at least two of the fluorine-containing groups are separated by a linking group having 2 or more carbon atoms (4) Polymerizable monomer group represented by the following general formula
(In the general formula, R ¹ represents a hydrogen atom, an alkyl group or a halogen atom, and Z represents a group containing an aromatic group, or a group having an alicyclic hydrocarbon group. (When the body (Ax) is liquid at 25 ° C., the viscosity at 25 ° C. is 500 mPa · s or less.)
(5) Polymerizable monomer group represented by the following general formula
(In the general formula, X ^{1 to} X ³ each independently represents a single bond or a linking group. Me represents a methyl group.)
(6) Polymerizable monomer group represented by the following general formula
[In the formula, Ar represents an arylene group which may have a substituent or an alicyclic hydrocarbon group which may have a substituent, X represents a single bond or an organic linking group, and R ¹ represents Represents a hydrogen atom or a methyl group, and n represents 2 or 3. ]
Details of these polymerizable monomers will be described later in the column of polymerizable monomers contained in the photocurable composition.

The total content of polymerizable monomers contained in the maintenance liquid of the present invention is preferably 5 to 100% by mass, more preferably 20 to 100% by mass, and still more preferably 40 to 100% by mass. By blending in such a range, the pattern transferability tends to be improved.
Further, as described above, the maintenance liquid of the present invention preferably contains a polymerizable monomer, but preferably contains substantially no polymer containing at least one kind of the polymerizable monomer as a repeating unit. . This is particularly effective when the polymerizable monomer is bifunctional or higher.
The polymer containing a polymerizable monomer as a repeating unit means that the polymerizable monomers are produced at the time of production and storage of the polymerizable monomer, and further at the time of production and storage of the photocurable composition. It represents a so-called “impurity polymer” that is produced by polymerization. Therefore, it is completely different from polymer additives such as surfactants.
Here, “substantially not containing a polymer” means, for example, a component derived from a polymerizable monomer having a molecular weight larger than that of the polymerizable monomer in gel permeation chromatography (GPC) measurement of the polymerizable monomer. The area ratio (peak ratio) is 0.5% or less with respect to the polymerizable monomer component, preferably 0.1% or less, and more preferably below the detection limit.

In gel permeation chromatography (GPC) measurement of a polymerizable monomer, a very small amount of a polymer component that cannot be detected by an RI detector can be detected with high sensitivity by using a light scattering detector. As a light scattering detector, both a laser light scattering detector and an evaporative light scattering detector (ELSD) can detect a polymer component with higher sensitivity than an RI detector, but more preferably, a polymer component can be detected with higher sensitivity. A preferred laser light scattering detector is preferred. In other words, since the scattering intensity of light scattering increases as the particle size increases, when a laser light scattering detector is used in GPC measurement, a polymer having a higher molecular weight is observed as a larger peak, and therefore the actual polymer content is detected by RI. Even a trace amount that cannot be detected by an instrument can be detected with high sensitivity as a large peak. As the laser light scattering detector, a multi-angle light scattering detector (MALS) that can be observed at many detection angles is commercially available.
As a preferred embodiment, the area ratio (peak) of components derived from a polymerizable monomer having a molecular weight larger than that of the polymerizable monomer when measured using a laser light scattering detector in GPC measurement of the polymerizable monomer. Ratio) is usually 50% or less with respect to the polymerizable monomer component, more preferably 30% or less, still more preferably 10% or less, and particularly preferably below the detection limit. is there.
When the maintenance liquid of the present invention contains two or more kinds of polymerizable monomers, the polymer containing the polymerizable monomer as a repeating unit includes two kinds other than the polymer derived from each polymerizable monomer. Copolymers derived from the above polymerizable monomers are also included.
As a result of the study by the present inventor, a polymerizable monomer containing a polymerizable monomer and a polymer containing the polymerizable monomer as a repeating unit, such as those sold as a commercially available polymerizable monomer From the composition, it was found that trace amounts of polymer impurities were difficult to detect by GPC. It was also found that even a trace amount of polymer that cannot be detected by GPC affects the imprint pattern. From this point of view, the polymerizable monomer composition contains the polymerizable monomer in a solvent in which the polymerizable monomer is soluble and the polymer containing the polymerizable monomer as a repeating unit is insoluble or hardly soluble. It is preferable that the turbidity of the solution when the monomer composition is mixed at a concentration of 10% by mass is 1000 ppm or less. The turbidity is more preferably 700 ppm or less, further preferably 500 ppm or less, still more preferably 100 ppm or less, particularly preferably 10 ppm or less, and most preferably 1 ppm or less.

Here, the solvent in which a polymer containing a polymerizable monomer as a repeating unit is insoluble or hardly soluble means a solvent having a polymer component solubility of 1% by mass or less, and is a hydrocarbon solvent (for example, pentane, hexane). , Heptane, toluene, xylene, benzene) or a solvent containing an alcohol solvent (for example, methanol, ethanol, 1- or 2-propanol, 1- or 2-butanol) is preferable.
The polymer component in the above represents a component having a molecular weight larger than that of the polymerizable monomer, and includes a so-called oligomer. Preferably, it is a component having a weight average molecular weight of 10,000 or more in GPC, more preferably a weight average molecular weight of 30,000 or more, and preferably a weight average molecular weight of 50,000 or more. In particular, when a polymer having a large molecular weight is contained, the pattern transferability during imprinting is deteriorated.
As the step of removing the impurity polymer, a publicly known method can be widely adopted, but the polymerizable monomer is soluble, and the polymer containing the polymerizable monomer as a repeating unit is insoluble or hardly soluble, and It is preferable to remove through a step of mixing the polymerizable monomer composition to precipitate a polymer. As a solvent in which a polymer containing a polymerizable monomer composition as a repeating unit is insoluble or hardly soluble, a hydrocarbon solvent (eg, pentane, hexane, heptane, toluene, xylene, benzene) or an alcohol solvent (eg, methanol) , Ethanol, 1- or 2-propanol, 1- or 2-butanol). The concentration to be mixed is preferably 1 to 99% by mass, more preferably 3 to 50% by mass, further preferably 5 to 30% by mass, and most preferably 5 to 20% by mass as the concentration of the polymerizable monomer composition. .
After the step of precipitating the polymer, usually, the precipitated polymer is further removed. As a removal method, a filtration method is preferable. As the filtration medium, filter paper, filter, silica gel, alumina, celite and the like are preferable, and a filter is preferable. As the filter material, polytetrafluoroethylene, polyethylene, nylon and the like are preferable. The filter size is preferably 0.005 μm to 10 μm, more preferably 0.01 μm to 1 μm.

The maintenance liquid of the present invention is preferably a compound in which 80% by mass or more of the total composition is a compound having a boiling point of 100 ° C. or more at 1 atm, more preferably a boiling point at 1 atm, from the viewpoint of suppressing the precipitation of foreign matters due to volatilization and suppressing the mixing of bubbles. Is a compound having a temperature of 120 ° C. or higher, more preferably a compound having a boiling point of 150 ° C. or higher at 1 atm. The upper limit is not particularly defined, but is usually 500 ° C. or lower.
Furthermore, in the present invention, the amount of dissolved oxygen in the maintenance liquid is preferably 45 mg / l to 10 mg / l. When a maintenance liquid with a large amount of dissolved oxygen is used for cleaning the inkjet device member, minute bubbles are likely to be generated inside the inkjet device. If the photocurable composition is discharged after washing while the bubbles generated from the maintenance liquid remain inside, the bubbles are applied to the photocurable composition when pressure is applied to the photocurable composition. Therefore, a normal discharge state cannot be obtained. In addition, when minute bubbles generated from dissolved oxygen in the maintenance liquid are generated inside the ink jet device, oxygen is contained in the photocurable composition to be discharged, and the polymerizable monomer in the photocurable composition is polymerized. In this case, the radical active species is deactivated, and a sufficient amount of radicals for the polymerization reaction of the polymerizable monomer cannot be supplied. As a result, the curing reaction of the photocurable composition becomes insufficient. In order to avoid such problems, in the present invention, the amount of dissolved oxygen in the maintenance liquid is set to 45 mg / l to 10 mg / l, and polymerization inhibition can be effectively suppressed.
The viscosity at 25 ° C. of the maintenance liquid of the present invention is preferably 50 mPa · s or less, more preferably 30 mPa · s or less, and further preferably 20 mPa · s or less. The lower limit is not particularly defined, but is usually 1 mPa · s or more.
The maintenance liquid for the inkjet discharge apparatus of the present invention is preferably non-aqueous, and the water content is preferably 10% by mass or less, more preferably 5% by mass or less.

  The maintenance liquid for the inkjet discharge apparatus of the present invention may further contain various additives. As the additives, surfactants, antifoaming agents, stabilizers, antioxidants, polymerization inhibitors and the like are preferable. The content of these additives is preferably 0 to 20% by mass. In addition, the maintenance liquid of the present invention may contain a photopolymerization initiator, but preferably does not contain a photopolymerization initiator.

  In particular, the maintenance liquid of the present invention is preferably composed of 0 to 95% by mass of a compound having an ester and / or ether functional group, 5 to 100% by mass of (meth) acrylate, and 20% by mass or less of other components. .

Inkjet Discharge Method In the present invention, since the photocurable composition is used as an inkjet discharge liquid, it is photocurable at a discharge temperature (for example, 20 to 80 ° C., preferably 20 to 60 ° C.) in consideration of the discharge property. The viscosity of the composition is 5 to 30 mPa · s, more preferably 5 to 20 mPa · s. For example, in the present invention, the viscosity of the photocurable composition at 25 ° C. is preferably 5 to 100 mPa · s, more preferably 5 to 50 mPa · s. In the present invention, it is preferable that the composition ratio of the photocurable composition is appropriately adjusted so that the viscosity is in the above range.
In addition, the description of Unexamined-Japanese-Patent No. 2007-254546 can be employ | adopted for the inkjet discharge method, unless it deviates from the meaning of this invention.

  In the present invention, the surface tension of the photocurable composition is preferably 20 to 40 mN / m, more preferably 22 to 38 mN / m, and still more preferably 24 to 36 mN / m from the viewpoint of dischargeability and wettability to the substrate. m.

Inkjet device The inkjet device used in the present invention is not particularly limited, and a commercially available inkjet device can be used. That is, in the present invention, recording can be performed on a recording medium using a commercially available inkjet apparatus. Examples of the ink jet apparatus that can be used in the present invention include an ink supply system and a temperature sensor. The ink supply system includes, for example, an original tank containing the photocurable composition used in the present invention, a supply pipe, an ink supply tank immediately before the inkjet head, a filter, and a piezo-type inkjet head. The piezo-type ink jet head can be driven so as to be ejected at 1 to 100 pl, preferably 1 to 20 pl.

  As described above, since it is desirable that the photocurable composition as the ink has a constant temperature for the photocurable composition to be ejected, the ink supply tank to the inkjet head portion are insulated and / or heated. It can be performed. The temperature control method is not particularly limited, but for example, it is preferable to provide a plurality of temperature sensors at each piping site and perform heating control according to the ink flow rate and the environmental temperature. The temperature sensor can be provided in the vicinity of the ink supply tank and the nozzle of the inkjet head. Moreover, it is preferable that the head unit to be heated is thermally shielded or insulated so that the apparatus main body is not affected by the temperature from the outside air. In order to shorten the startup time of the inkjet apparatus required for heating or to reduce the loss of thermal energy, it is preferable to insulate from other parts and reduce the heat capacity of the entire heating unit.

  Next, a maintenance method for the inkjet apparatus will be described. As a method of using the maintenance liquid of the present invention, it is preferable to use it as a filling liquid in an ink jet apparatus, preferably in the cleaning of the head and in the apparatus when not used. The inkjet device or some parts are cleaned using the maintenance liquid of the present invention. As a cleaning method, a method of wiping the inkjet apparatus or its parts with a cloth or a cleaning blade wetted with the maintenance liquid of the present invention, a method of immersing the inkjet apparatus or its parts in the maintenance liquid of the present invention, and an ink jet of the maintenance liquid of the present invention. A method in which an absorbent is brought into contact with an inkjet device or a component thereof after being applied to the device or the component thereof, and the maintenance liquid is sucked by the absorbent material, and after the maintenance liquid of the present invention is applied to the inkjet device or the component, the inkjet device or the component thereof For example, a method of removing maintenance liquid by performing air suction, air supply, or the like.

  In the case where a cleaning mechanism for cleaning the head of the ink jet apparatus with the maintenance liquid is provided in the ink jet apparatus, the head is cleaned by the cleaning mechanism when the maintenance liquid of the present invention is supplied to the cleaning mechanism. Further, when the discharge port of the head is covered with a cap, a cap coated with the maintenance liquid of the present invention may be used.

  Further, the inside of the head and the vicinity of the nozzle can be cleaned by filling the maintenance liquid of the present invention into the head of the ink jet apparatus and discharging it from the nozzle. In this case, it is preferable to apply a pressure of about 1 kPa to 100 kPa. Specifically, the maintenance liquid is fed into the head from an ink supply path connected to the head. At that time, the pressure may be adjusted to discharge the maintenance liquid from the nozzle, or the maintenance liquid may be forcibly sucked from the nozzle surface with a rubber tube or the like so as not to damage the nozzle surface. In some cases, the maintenance liquid can be discharged by driving the apparatus head and performing the same operation as the ink ejection. On the other hand, a method of cleaning the inside of the apparatus (nozzle, head, tube, pump, etc.) by circulating the maintenance liquid can also be exemplified. Alternatively, the maintenance liquid may be discharged or collected after filling the head with maintenance liquid and applying external vibration by ultrasonic waves to promote the solubility of the solid content in the head.

  In the present invention, when the inkjet apparatus is not used for several hours, the inkjet apparatus is preferably used by filling the maintenance liquid of the present invention in the head of the inkjet apparatus. Thus, it is preferable to fill the head with the maintenance liquid of the present invention because the curing of the photocurable ink can be prevented and the clogging of the head can be suppressed. Further, it is preferable that the head is automatically cleaned with the maintenance liquid when the discharge is not performed for a certain time or more (preferably 12 to 168 hours, more preferably 24 to 36 hours), and the head after cleaning is maintained. More preferably, it is filled with a liquid. In use, the photocurable ink can be discharged by discharging or collecting the filled maintenance liquid.

(Photocurable composition)
Next, the photocurable composition in the present invention will be described.
The photocurable composition in the present invention contains a polymerizable monomer, and usually contains a polymerizable monomer and a photopolymerization initiator. Although the kind of the polymerizable monomer used for the photocurable composition used for this invention is not specifically defined unless it deviates from the meaning of this invention, for example, it has 1-6 ethylenically unsaturated bond containing groups. Polymerizable unsaturated monomers; epoxy compounds, oxetane compounds; vinyl ether compounds; styrene derivatives; compounds having fluorine atoms; propenyl ethers or butenyl ethers.

  The polymerizable unsaturated monomer having 1 to 6 ethylenically unsaturated bond-containing groups (1 to 6 functional polymerizable unsaturated monomer) will be described.

  First, specific examples of the polymerizable unsaturated monomer having one ethylenically unsaturated bond-containing group include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, N-vinylpyrrolidinone, 2 -Acryloyloxyethyl phthalate, 2-acryloyloxy 2-hydroxyethyl phthalate, 2-acryloyloxyethyl hexahydrophthalate, 2-acryloyloxypropyl phthalate, 2-ethyl-2-butylpropanediol acrylate, 2-ethylhexyl (meta ) Acrylate, 2-ethylhexyl carbitol (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) Acrylate, acrylic acid dimer, benzyl (meth) acrylate, 1- or 2-naphthyl (meth) acrylate, butoxyethyl (meth) acrylate, cetyl (meth) acrylate, ethylene oxide modified (hereinafter referred to as “EO”) cresol (meth) Acrylate, dipropylene glycol (meth) acrylate, ethoxylated phenyl (meth) acrylate, isooctyl (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentanyloxy Ethyl (meth) acrylate, isomyristyl (meth) acrylate, lauryl (meth) acrylate, methoxydipropylene glycol (meth) acrylate, methoxytripropy Glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, methoxytriethylene glycol (meth) acrylate, neopentyl glycol benzoate (meth) acrylate, nonylphenoxypolyethylene glycol (meth) acrylate, nonylphenoxypolypropylene glycol (meth) acrylate , Octyl (meth) acrylate, paracumylphenoxyethylene glycol (meth) acrylate, epichlorohydrin (hereinafter referred to as “ECH”) modified phenoxy acrylate, phenoxyethyl (meth) acrylate, phenoxydiethylene glycol (meth) acrylate, phenoxyhexaethylene glycol (Meth) acrylate, phenoxytetraethylene glycol (meth) acrylate, polyethylene glycol Cole (meth) acrylate, polyethylene glycol-polypropylene glycol (meth) acrylate, polypropylene glycol (meth) acrylate, stearyl (meth) acrylate, EO modified succinic acid (meth) acrylate, tribromophenyl (meth) acrylate, EO modified tribromo Examples include phenyl (meth) acrylate, tridodecyl (meth) acrylate, p-isopropenylphenol, N-vinylpyrrolidone, and N-vinylcaprolactam.

  Among the monofunctional polymerizable monomers containing the ethylenically unsaturated bond, in the present invention, it is preferable to use a monofunctional (meth) acrylate compound from the viewpoint of photocurability. Examples of the monofunctional (meth) acrylate compound include monofunctional (meth) acrylate compounds in the monofunctional polymerizable monomer containing the ethylenically unsaturated bond.

  Among the monofunctional (meth) acrylate compounds, a monofunctional (meth) acrylate having an aromatic structure and / or an alicyclic hydrocarbon structure is preferable from the viewpoint of dry etching resistance, and a monofunctional (meta) having an aromatic structure ) Acrylate is more preferred.

  Among monofunctional (meth) acrylates having such an aromatic structure and / or alicyclic hydrocarbon structure, benzyl (meth) acrylate, benzyl (meth) acrylate having a substituent on the aromatic ring (preferred as a substituent) Is an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a cyano group), 1- or 2-naphthyl (meth) acrylate, 1- or 2-naphthylmethyl (meth) acrylate, 1- or 2 -Naphtylethyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentanyloxyethyl (meth) acrylate, isobornyl (meth) acrylate, adamantyl (meth) acrylate are preferred, benzyl (meth) acrylate, aromatic ring Benzyl (meth) acrylate having a substituent thereon, More preferably a monofunctional (meth) acrylate compound having a Futaren structure, 1- or 2-naphthyl (meth) acrylate, 1- or 2-naphthylmethyl (meth) acrylate are particularly preferred.

In the present invention, it is also preferable to use a polyfunctional polymerizable unsaturated monomer having two or more ethylenically unsaturated bond-containing groups as the polymerizable monomer.
Examples of the bifunctional polymerizable unsaturated monomer having two ethylenically unsaturated bond-containing groups that can be preferably used in the present invention include diethylene glycol monoethyl ether (meth) acrylate, dimethylol dicyclopentane di (meta ) Acrylate, di (meth) acrylated isocyanurate, 1,3-butylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, EO-modified 1,6-hexanediol di (meth) acrylate, ECH modified 1,6-hexanediol di (meth) acrylate, allyloxy polyethylene glycol acrylate, 1,9-nonanediol di (meth) acrylate, EO modified bisphenol A di (meth) acrylate, PO modified bisphenol A di (meth) Acrylate, modified screw Enol A di (meth) acrylate, EO modified bisphenol F di (meth) acrylate, ECH modified hexahydrophthalic acid diacrylate, hydroxypivalic acid neopentyl glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, EO modified Neopentyl glycol diacrylate, propylene oxide (hereinafter referred to as “PO”) modified neopentyl glycol diacrylate, caprolactone modified hydroxypivalate ester neopentyl glycol, stearic acid modified pentaerythritol di (meth) acrylate, ECH modified phthalic acid di ( (Meth) acrylate, poly (ethylene glycol-tetramethylene glycol) di (meth) acrylate, poly (propylene glycol-tetramethylene glycol) Di) (di) (meth) acrylate, polyester (di) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, ECH modified propylene glycol di (meth) acrylate, silicone di (meth) acrylate, triethylene Glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, dimethylol tricyclodecane di (meth) acrylate, neopentyl glycol modified trimethylolpropane di (meth) acrylate, tripropylene glycol di (meth) acrylate, EO Modified tripropylene glycol di (meth) acrylate, triglycerol di (meth) acrylate, dipropylene glycol di (meth) acrylate, divinyl ethyl And urea, divinylpropylene urea, o-, m-, p-xylylene di (meth) acrylate, 1,3-adamantane diacrylate norbornane dimethanol diacrylate.

  Among these, neopentyl glycol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, tripropylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, neopentyl hydroxypivalate Bifunctional (meth) such as glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, o-, m-, p-benzenedi (meth) acrylate, o-, m-, p-xylylene di (meth) acrylate Acrylate is preferably used in the present invention.

  Examples of the polyfunctional polymerizable unsaturated monomer having three or more ethylenically unsaturated bond-containing groups include ECH-modified glycerol tri (meth) acrylate, EO-modified glycerol tri (meth) acrylate, PO-modified glycerol tri (meta) ) Acrylate, pentaerythritol triacrylate, EO modified phosphoric acid triacrylate, trimethylolpropane tri (meth) acrylate, caprolactone modified trimethylolpropane tri (meth) acrylate, EO modified trimethylolpropane tri (meth) acrylate, PO modified trimethylol Propane tri (meth) acrylate, tris (acryloxyethyl) isocyanurate, dipentaerythritol hexa (meth) acrylate, caprolactone-modified dipentaerythritol hexa (meth) Acrylate, dipentaerythritol hydroxypenta (meth) acrylate, alkyl-modified dipentaerythritol penta (meth) acrylate, dipentaerythritol poly (meth) acrylate, alkyl-modified dipentaerythritol tri (meth) acrylate, ditrimethylolpropane tetra (meth) Examples include acrylate, pentaerythritol ethoxytetra (meth) acrylate, and pentaerythritol tetra (meth) acrylate.

  Among these, EO-modified glycerol tri (meth) acrylate, PO-modified glycerol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, EO-modified trimethylolpropane tri (meth) acrylate, PO-modified trimethylolpropane tri Trifunctional or higher functional (meth) acrylates such as (meth) acrylate, dipentaerythritol hexa (meth) acrylate, pentaerythritol ethoxytetra (meth) acrylate and pentaerythritol tetra (meth) acrylate are preferably used in the present invention.

  Among the polyfunctional polymerizable unsaturated monomers having two or more ethylenically unsaturated bonds, it is preferable in the present invention to use a polyfunctional (meth) acrylate from the viewpoint of photocurability. The polyfunctional (meth) acrylate referred to here is a generic term for the bifunctional (meth) acrylate and the trifunctional or higher functional (meth) acrylate. Specific examples of the polyfunctional (meth) acrylate include those exemplified in the polyfunctional polymerizable unsaturated monomer having two ethylenically unsaturated bonds, and those having three or more ethylenically unsaturated bonds. Various polyfunctional (meth) acrylates exemplified in the functional polymerizable unsaturated monomer can be exemplified.

  Examples of the compound having an oxirane ring (epoxy compound) include polyglycidyl esters of polybasic acids, polyglycidyl ethers of polyhydric alcohols, polyglycidyl ethers of polyoxyalkylene glycol, and polyglycidyl ethers of aromatic polyols. Examples include teters, hydrogenated compounds of polyglycidyl ethers of aromatic polyols, urethane polyepoxy compounds, and epoxidized polybutadienes. These compounds can be used alone or in combination of two or more thereof.

  As the compound having an oxirane ring (epoxy compound) that can be preferably used in the present invention, those described in paragraph No. 0053 of JP-A-2009-73078 can be preferably used.

  In particular, bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, hydrogenated bisphenol F diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, Glycerin triglycidyl ether, trimethylolpropane triglycidyl ether, neopentyl glycol diglycidyl ether, polyethylene glycol diglycidyl ether, and polypropylene glycol diglycidyl ether are preferred.

  As a commercially available product that can be suitably used as the glycidyl group-containing compound, those described in paragraph No. 0055 of JP-A-2009-73078 can be preferably employed. These can be used alone or in combination of two or more.

  The production method of these compounds having an oxirane ring is not limited. For example, Maruzen KK Publishing, 4th edition Experimental Chemistry Course 20 Organic Synthesis II, 213, 1992, Ed. By Alfred Hasfner, The chemistry of cyclic compounds-Small Ring Heterocycles part 3 Oxiranes, John & Wiley and Sons, An Interscience Publication, New York, 1985, Yoshimura, Adhesion, Vol. 29, No. 12, 32, 1985, Yoshimura, Adhesion, Vol. 30, No. 5, 42, 1986, Yoshimura, Adhesion, Vol. 30, No. 7, 42, 1986, Japanese Patent Application Laid-Open No. 11-1000037, Japanese Patent No. 2906245, Japanese Patent No. 2926262 and the like can be synthesized.

  As a polymerizable monomer that can be used in the present invention, a vinyl ether compound may be used in combination. As the vinyl ether compound, known compounds can be appropriately selected. For example, 2-ethylhexyl vinyl ether, butanediol-1,4-divinyl ether, diethylene glycol monovinyl ether, diethylene glycol monovinyl ether, ethylene glycol divinyl ether, triethylene glycol divinyl ether, 1,2-propanediol divinyl ether, 1,3-propanediol divinyl ether, 1,3-butanediol divinyl ether, 1,4-butanediol divinyl ether, tetramethylene glycol divinyl ether, neopentyl glycol divinyl ether, trimethylol Propane trivinyl ether, trimethylol ethane trivinyl ether, hexanediol divinyl ether, tetra Tylene glycol divinyl ether, pentaerythritol divinyl ether, pentaerythritol trivinyl ether, pentaerythritol tetravinyl ether, sorbitol tetravinyl ether, sorbitol pentavinyl ether, ethylene glycol diethylene vinyl ether, triethylene glycol diethylene vinyl ether, ethylene glycol dipropylene vinyl ether, triethylene glycol diethylene vinyl ether , Trimethylolpropane triethylene vinyl ether, trimethylolpropane diethylene vinyl ether, pentaerythritol diethylene vinyl ether, pentaerythritol triethylene vinyl ether, pentaerythritol tetraethylene vinyl ether, 1,1,1-to Scan [4- (2-vinyloxy ethoxy) phenyl] ethane, bisphenol A divinyloxyethyl carboxyethyl ether.

  These vinyl ether compounds can be obtained, for example, by the method described in Stephen C. Lapin, Polymers Paint Color Journal. 179 (4237), 321 (1988), that is, the reaction of a polyhydric alcohol or polyhydric phenol with acetylene, or They can be synthesized by the reaction of a polyhydric alcohol or polyhydric phenol and a halogenated alkyl vinyl ether, and these can be used singly or in combination of two or more.

  As described above, at least one of the polymerizable monomers contained in the photocurable composition in the present invention, together with at least one of the polymerizable monomers contained in the maintenance liquid, is respectively a specific common compound group. When included, the effect of the present invention is more effectively exhibited. Hereinafter, these compounds will be described in detail.

(1) (Meth) acrylate group having an aromatic group and / or an alicyclic hydrocarbon group As the compound contained in this compound group, an aromatic group (meth) acrylate is preferable, and a benzene ring and / or a naphthalene ring are included. (Meth) acrylate having is more preferable.
As an example, compounds corresponding to the following compound groups (4) to (7) are exemplified.
Although there is no restriction | limiting in particular in content of this polymerizable monomer in the photocurable composition used for this invention, 10-100 mass% is preferable in all the polymeric compounds, and 30-100 mass% is more. Preferably, 50-100 mass% is further more preferable, and 70-100 mass% is especially preferable.

(2) Polymerizable compound group having at least one of fluorine atom and silicon atom The polymerizable compound having at least one of fluorine atom and silicon atom is a fluorine atom, a silicon atom or a functional group having both fluorine atom and silicon atom. A compound having at least one group and at least one polymerizable functional group.

  Although there is no restriction | limiting in particular in content in the photocurable composition used for this invention, From a viewpoint of sclerosis | hardenability improvement and a viewpoint of composition viscosity, 0.1-100 mass% in all the polymeric compounds. Is preferable, 0.2-50 mass% is more preferable, 0.5-20 mass% is further more preferable, and 1-10 mass% is especially preferable.

(A) Polymerizable compound having fluorine atom The fluorine-containing group selected from a fluoroalkyl group and a fluoroalkyl ether group is preferred as the group having a fluorine atom that the polymerizable compound having a fluorine atom has.
The fluoroalkyl group is preferably a fluoroalkyl group having 2 or more carbon atoms, more preferably a fluoroalkyl group having 4 or more carbon atoms, and the upper limit is not particularly defined, but 20 or less is preferable. 8 or less is more preferable, and 6 or less is more preferable. Most preferably, it is a C4-C6 fluoroalkyl group. Examples of the preferred fluoroalkyl group include a trifluoromethyl group, a pentafluoroethyl group, a heptafluoropropyl group, a hexafluoroisopropyl group, a nonafluorobutyl group, a tridecafluorohexyl group, and a heptadecafluorooctyl group.

  The polymerizable compound having at least one of the fluorine atom and the silicon atom is preferably a polymerizable compound having a fluorine atom having a trifluoromethyl group. That is, at least one of the fluoroalkyl groups preferably contains a trifluoromethyl group structure. By having a trifluoromethyl group structure, the effect of the present invention is manifested even with a small addition amount (for example, 10% by mass or less), so that compatibility with other components is improved, and line edge roughness after dry etching is improved. improves.

As in the case of the fluoroalkyl group, the fluoroalkyl ether group preferably has a trifluoromethyl group, and preferably contains a perfluoroethyleneoxy group or a perfluoropropyleneoxy group. A fluoroalkyl ether unit having a trifluoromethyl group such as — (CF (CF ₃ ) CF ₂ O) — and / or a trifluoromethyl ether group having a trifluoromethyl group at the terminal thereof are preferred.

  The number of total fluorine atoms contained in the polymerizable compound having fluorine atoms is preferably 3 to 60, more preferably 5 to 40, and further preferably 9 to 26 per molecule in the case of a non-polymer compound. .

  In the case of a non-polymer compound, the polymerizable compound having a fluorine atom is preferably a polymerizable compound having a fluorine atom with a fluorine content defined below of 30 to 60%, more preferably 35 to 55%. Yes, more preferably 35-50%. When the polymerizable compound having a fluorine atom is a polymer compound, it is preferably a polymerizable compound having a fluorine atom with a fluorine content defined below of 10 to 50%, more preferably 15 to 40%, More preferably, it is 20 to 30%. By making the fluorine content within the proper range, mold contamination can be reduced and compatibility with other components can be improved, so that line edge roughness after dry etching can be improved, and high aspect pattern formability and repetitive patterns can be obtained. Formability is improved. In the present specification, the fluorine content is represented by the following formula.

  A preferred example of the polymerizable compound having a fluorine atom is a compound having a partial structure represented by the following general formula (I). By adopting a compound having such a partial structure, the pattern forming property is excellent and the temporal stability of the photocurable composition is improved.

Formula (I)
In general formula (I), n represents an integer of 1 to 8, preferably an integer of 4 to 6.

  Another preferred example of the polymerizable compound having a fluorine atom is a compound having a partial structure represented by the following general formula (II). Of course, you may have both the partial structure represented by general formula (I), and the partial structure represented by general formula (II).

Formula (II)
In the general formula (II), L ¹ represents a single bond or an alkylene group having 1 to 8 carbon atoms, L ² represents an alkylene group having 1 to 8 carbon atoms, and m1 and m2 each represents 0 or 1 And at least one of m1 and m2 is 1. m3 represents an integer of 1 to 3, p represents an integer of 1 to 8, and when m3 is 2 or more, each -C _p F _{2p + 1} may be the same or different. .
L ¹ and L ² are each preferably an alkylene group having 1 to 4 carbon atoms. Further, the alkylene group may have a substituent within a range not departing from the gist of the present invention. The m3 is preferably 1 or 2. The p is preferably an integer of 4-6.

  Although the specific example of the polymeric compound which has a fluorine atom used with the photocurable composition used for this invention below is given, this invention is not limited to these.

Examples of the polymerizable compound having a fluorine atom include trifluoroethyl (meth) acrylate, pentafluoroethyl (meth) acrylate, (perfluorobutyl) ethyl (meth) acrylate, perfluorobutyl-hydroxypropyl (meth) acrylate, ( Monofunctional having fluorine atoms such as perfluorohexyl) ethyl (meth) acrylate, octafluoropentyl (meth) acrylate, perfluorooctylethyl (meth) acrylate, tetrafluoropropyl (meth) acrylate, hexafluoropropyl (meth) acrylate, etc. A polymerizable compound is mentioned. Examples of the polymerizable compound having a fluorine atom include 2,2,3,3,4,4-hexafluoropentane di (meth) acrylate, 2,2,3,3,4,4,5,5- A polyfunctional polymerizable compound having two or more polymerizable functional groups having a di (meth) acrylate having a fluoroalkylene group such as octafluorohexane di (meth) acrylate is also preferred.
More preferably, it is a compound corresponding to the compound group (3).

(B) Polymerizable compound having silicon atom Examples of the structure of the functional group having a silicon atom include a trialkylsilyl group, a chain siloxane structure, a cyclic siloxane structure, and a cage siloxane structure. From the viewpoints of solubility and mold releasability, a functional group having a trimethylsilyl group or a dimethylsiloxane structure is preferred.

Although the specific example of the polymeric compound which has the said silicon atom used with the photocurable composition used for this invention below is given, this invention is not limited to these.
Examples of the polymerizable compound having a silicon atom include 3-tris (trimethylsilyloxy) silylpropyl (meth) acrylate, trimethylsilylethyl (meth) acrylate, alkyl (meth) acrylate substituted with polydimethylsiloxane, and polydimethylsiloxane structure. Examples include di (meth) acrylate.

(3) Compound group containing at least two fluorine-containing groups selected from a fluoroalkyl group and a fluoroalkyl ether group, and at least two of the fluorine-containing groups are separated by a linking group having 2 or more carbon atoms Compound containing at least two fluorine-containing groups selected from a fluoroalkyl group and a fluoroalkyl ether group, and at least two of the fluorine-containing groups are separated by a linking group having 2 or more carbon atoms The body is a compound containing at least two fluorine-containing groups selected from a fluoroalkyl group and a fluoroalkyl ether group, and at least two of the fluorine-containing groups are separated by a linking group having 2 or more carbon atoms. is there.
The fluoroalkyl group is preferably a fluoroalkyl group having 2 or more carbon atoms, more preferably a fluoroalkyl group having 4 or more carbon atoms, and the upper limit is not particularly defined, but 20 or less is preferable. 8 or less is more preferable, and 6 or less is more preferable. Most preferably, it is a C4-C6 fluoroalkyl group. In addition, at least two of the fluoroalkyl groups preferably contain a trifluoromethyl group structure. By having a plurality of trifluoromethyl group structures, the effects of the present invention are exhibited even with a small addition amount (for example, 10% by mass or less), so that compatibility with other components is improved, and line edge roughness after dry etching is improved. Will improve.
From the same viewpoint, a compound containing three or more trifluoromethyl group structures in the polymerizable monomer is also preferable. More preferred are compounds containing 3 to 9, more preferably 4 to 6 trifluoromethyl group structures. Examples of the compound containing three or more trifluoromethyl group structures include a branched fluoroalkyl group having two or more trifluoromethyl groups in one fluorine-containing group, such as —CH (CF ₃ ) ₂ group, —C (CF ₃ ) A compound having a fluoroalkyl group such as ₃ or —CCH ₃ (CF ₃ ) ₂ CH ₃ group is preferred.

As the fluoroalkyl ether group, those having a trifluoromethyl group are preferred, and those containing a perfluoroethyleneoxy group or a perfluoropropyleneoxy group are preferred. A fluoroalkyl ether unit having a trifluoromethyl group such as — (CF (CF ₃ ) CF ₂ O) — and / or a trifluoromethyl ether group having a trifluoromethyl group at the terminal thereof are preferred.
The number of total fluorine atoms contained in the polymerizable monomer is preferably 6 to 60, more preferably 9 to 40, and still more preferably 12 to 40.
The polymerizable monomer has a fluorine content as defined above, preferably 30 to 60%, more preferably 35 to 55%, and still more preferably 35 to 50%. By making the fluorine content within an appropriate range, mold contamination can be reduced and the line edge roughness after dry etching is improved.

At least two of the fluorine-containing groups of the polymerizable monomer are separated by a linking group having 2 or more carbon atoms. That is, when the polymerizable monomer has two fluorine-containing groups, the two fluorine-containing groups are separated by a linking group having 2 or more carbon atoms. When the polymerizable monomer has three or more fluorine-containing groups, at least two of them are separated by a linking group having 2 or more carbon atoms, and the remaining fluorine-containing groups have any bonding form. May be. The linking group having 2 or more carbon atoms is a linking group having at least two carbon atoms that are not substituted with fluorine atoms.
Examples of the functional group contained in the linking group having 2 or more carbon atoms include groups containing at least one of an alkylene group, an ester group, a sulfide group, an arylene group, an amide group and a urethane group, and at least an ester group and It is more preferable to have a sulfide group. The linking group having 2 or more carbon atoms is preferably a group selected from an alkylene group, an ester group, a sulfide group, an arylene group, an amide group, a urethane group, and combinations thereof.
These groups may have a substituent without departing from the gist of the present invention.

As a preferred example of the polymerizable monomer, a compound represented by a general formula can be given.
In the general formula, Rf represents a functional group having a fluorine-containing group selected from a fluoroalkyl group and a fluoroalkyl ether group, and A ¹ represents a linking group. Y represents a polymerizable functional group, preferably a (meth) acrylic ester group, an epoxy group, or a vinyl ether group. x represents an integer of 1 to 4, preferably 1 or 2. When x is 2 or more, each Y may be the same or different.
A ¹ is preferably a linking group having an alkylene group and / or an arylene group, and may further contain a linking group containing a hetero atom. Examples of the linking group having a hetero atom include -O-, -C (= O) O-, -S-, -C (= O)-, and -NH-. These groups may have a substituent within a range not departing from the gist of the present invention, but preferably do not have a substituent. A ¹ preferably has 2 to 50 carbon atoms, and more preferably 4 to 15 carbon atoms.
A preferred example of the polymerizable monomer includes a compound having a partial structure represented by the following general formula. By adopting a compound having such a partial structure, the pattern forming property is excellent and the temporal stability of the photocurable composition is improved.
In general formula, n represents the integer of 1-8, Preferably it is an integer of 4-6.

Another preferred example of the polymerizable monomer includes a compound having a partial structure represented by the following general formula (II). Of course, you may have both the partial structure represented by general formula, and the partial structure represented by general formula (II).
In general formula (II), R ² and R ³ each represent an alkylene group having 1 to 8 carbon atoms, and each preferably an alkylene group having 1 to 4 carbon atoms. The alkylene group may have a substituent without departing from the spirit of the present invention.
m1 and m2 each represents 0 or 1, and at least one of m1 and m2 is 1. m3 represents an integer of 1 to 3, and is preferably 1 or 2. n represents an integer of 1 to 8, and an integer of 4 to 6 is preferable. When m3 is 2 or more, respectively, -C _n F _{2n + 1} may be different may be the same.

The polymerizable monomer is preferably a polymerizable monomer represented by the following general formula (III).
(In the general formula (III), R ¹ represents a hydrogen atom, an alkyl group, a halogen atom or a cyano group, A represents an (a1 + a2) -valent linking group, a1 represents an integer of 1 to 6. a2 represents 2 represents 6 integer, R ² and R ³ is .m1 and m2 each represents an alkylene group having 1 to 8 carbon atoms, 0 or 1, at least one of m1 and m2 is 1 .M3 is Represents an integer of 1 to 3. m4 and m5 each represents 0 or 1, at least one of m4 and m5 is 1, and when both m1 and m2 are 1, m4 is 1. n is Represents an integer of 1 to 8.)

R ¹ represents a hydrogen atom, an alkyl group, a halogen atom or a cyano group, preferably a hydrogen atom or an alkyl group, more preferably a hydrogen atom or a methyl group, and even more preferably a hydrogen atom.
A is a (a1 + a2) -valent linking group, preferably a linking group having an alkylene group and / or an arylene group, and may further contain a linking group containing a hetero atom. Examples of the linking group having a hetero atom include -O-, -C (= O) O-, -S-, -C (= O)-, and -NH-. These groups may have a substituent within a range not departing from the gist of the present invention, but preferably do not have a substituent. A preferably has 2 to 50 carbon atoms, and more preferably 4 to 15 carbon atoms.
R ² , R ³ , m 1, m ² , m 3 and n have the same meaning as in formula (II), and the preferred range is also the same.
a1 is an integer of 1 to 6, preferably 1 to 3, and more preferably 1 or 2.
a2 is an integer of 2 to 6, preferably 2 or 3, and more preferably 2.
When a1 is 2 or more, each A may be the same or different.
When a2 is 2 or more, R ² , R ³ , m1, m2, m3, m4, m5 and n may be the same or different.

  The molecular weight of the polymerizable monomer used in the present invention is preferably 500 to 2,000. More preferably, it is 600-1500, More preferably, it is 600-1200.

Although the specific example of the polymerizable monomer used with the photocurable composition used for this invention below is given, this invention is not limited to these. R ¹ in the following formula is each a hydrogen atom, an alkyl group, a halogen atom, or a cyano group.

(4) Polymerizable monomer group represented by the following general formula
(In the general formula, Z represents a group containing an aromatic group and having a molecular weight of 100 or more, and R ¹ represents a hydrogen atom, an alkyl group or a halogen atom, provided that the polymerizable monomer (Ax) is liquid at 25 ° C. When, the viscosity at 25 ° C. is 500 mPa · s or less.)
R ¹ is preferably a hydrogen atom or an alkyl group, preferably a hydrogen atom or a methyl group, and more preferably a hydrogen atom from the viewpoint of curability. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
Z is preferably an aralkyl group which may have a substituent, an aryl group which may have a substituent, or a group in which these groups are bonded via a linking group. The linking group here may include a linking group containing a hetero atom, and preferably a group consisting of —CH ₂ —, —O—, —C (═O) —, —S—, and combinations thereof. It is. The aromatic group contained in Z is preferably a phenyl group, and preferably contains only a phenyl group. Compared with polycyclic aromatic groups and heteroaromatic groups, the phenyl group alone has a lower viscosity and better pattern formation, and can suppress particle defects. The molecular weight of Z is preferably 100 to 300, more preferably 120 to 250.
The number of polymerizable groups and the number of aromatic groups contained in the polymerizable monomer are the number of polymerizable groups ≦ the aromatic group
Is preferable from the viewpoint of viscosity and dry etching resistance. At this time, a condensed aromatic ring such as naphthalene is counted as one aromatic group, and when two aromatic rings such as biphenyl are connected by breaking a bond, they are counted as two aromatic groups.
When the polymerizable monomer is liquid at 25 ° C., the viscosity at 25 ° C. is preferably 2 to 500 mPa · s, more preferably 3 to 200 mPa · s, and most preferably 3 to 100 mPa · s. The polymerizable monomer is preferably a liquid at 25 ° C., or even a solid, preferably having a melting point of 60 ° C. or less, and more preferably a liquid at 25 ° C.
Z is preferably a group represented by -Z ¹ -Z ² . Here, Z ¹ is a single bond or a hydrocarbon group, and the hydrocarbon group may include a linking group containing a hetero atom in the chain. Z ² is an aromatic group which may have a substituent and has a molecular weight of 90 or more.
Z ¹ is preferably a single bond or an alkylene group, and the alkylene group may contain a linking group containing a hetero atom in the chain. Z ¹ is more preferably an alkylene group that does not contain a linking group containing a hetero atom in the chain, and more preferably a methylene group or an ethylene group. Examples of the linking group containing a hetero atom include —O—, —C (═O) —, —S—, and a group composed of a combination of these with an alkylene group. Moreover, it is preferable that carbon number of a hydrocarbon group is 1-3.
Z ² is preferably an aromatic group having a substituent having a molecular weight of 15 or more. Examples of the aromatic group contained in Z ² include a phenyl group and a naphthyl group, and a more preferred example is a phenyl group having a substituent having a molecular weight of 15 or more. Z ² is preferably formed from a monocyclic aromatic group.
Z ² is also preferably a group in which two or more aromatic groups are linked directly or via a linking group. The linking group in this case is also preferably a group consisting of —CH ₂ —, —O—, —C (═O) —, —S—, and combinations thereof.

  Examples of the substituent that the aromatic group may have include, for example, a halogen atom (a fluorine atom, a chloro atom, a bromine atom, an iodine atom), a linear, branched or cyclic alkyl group, and an alkenyl group. , Alkynyl group, aryl group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, cyano group, carboxyl group, hydroxyl group, alkoxy group, aryloxy group, alkylthio group, arylthio group, heterocyclic oxy group, acyloxy group Amino group, nitro group, hydrazino group, heterocyclic group and the like. A group further substituted with these groups is also preferred.

The polymerizable monomer in the present invention is preferably liquid at 25 ° C., and when the polymerizable monomer is liquid at 25 ° C., the viscosity at 25 ° C. is 500 mPa · s or less. More preferably, the viscosity at 25 ° C. is 300 mPa · s or less, more preferably 200 mPa · s or less, and most preferably 100 mPa · s or less.
The addition amount of the compound represented by the general formula in the photocurable composition is preferably 10 to 100% by mass, more preferably 20 to 100% by mass, and 30 to 80% by mass. Is particularly preferred.

The compound represented by the general formula is preferably a compound represented by the following general formula (II).
(In the general formula (II), R ¹ represents a hydrogen atom, an alkyl group or a halogen atom, X ¹ is a single bond or a hydrocarbon group, and the hydrocarbon group is a linking group containing a hetero atom in the chain. Y ¹ represents a substituent having a molecular weight of 15 or more, and n1 represents an integer of 0 to 3. However, when n1 is 0, X ¹ is a hydrocarbon group having 2 or more carbon atoms. Ar represents an aromatic group or an aromatic linking group, and is preferably a phenyl group or a phenylene group.)

R ¹ has the same meaning as R ¹ in the formula, the preferred range is also the same.
X ¹ has the same meaning as Z ¹ described above, and the preferred range is also the same.
Y ¹ is a substituent having a molecular weight of 15 or more, and examples thereof include an alkyl group, an alkoxy group, an aryloxy group, an aralkyl group, an acyl group, an alkoxycarbonyl group, an alkylthio group, an arylthio group, and a halogen atom. These substituents may have further substituents.
When n1 is 0, X ¹ is preferably an alkylene group having 2 or 3 carbon atoms, and when n1 is 2, X ¹ is preferably a single bond or a hydrocarbon group having 1 carbon atom.
In particular, the preferred aspect at n1 is 1, X ¹ is an alkylene group having 1 to 3 carbon atoms.

The compound represented by the general formula (II) is more preferably a compound represented by the following general formula (III).
(In the general formula (III), R ¹ represents a hydrogen atom, an alkyl group or a halogen atom. X ¹ is a single bond or a hydrocarbon group, and the hydrocarbon group is a linking group containing a hetero atom in the chain. Y ¹ represents a substituent having a molecular weight of 15 or more, and n1 represents an integer of 0 to 3. However, when n1 is 0, X ¹ is a hydrocarbon group having 2 or more carbon atoms. is there.)
R ¹ has the same meaning as R ¹ in the formula, the preferred range is also the same.
X ¹ has the same meaning as Z ¹ described above, and the preferred range is also the same.
Y ¹ has the same meaning as Y ¹ in the general formula (II), and the preferred range is also the same.
n1 is synonymous with n1 in the said general formula (II), and its preferable range is also synonymous.

  The compound represented by the general formula (III) is more preferably a compound represented by any one of (IV) to (VI).

Compound represented by general formula (IV)
(In the general formula (IV), R ¹ represents a hydrogen atom, an alkyl group or a halogen atom. X ² is a single bond or a hydrocarbon group, and the hydrocarbon group contains a hetero atom in the chain. Y ² represents a substituent not having an aromatic group having a molecular weight of 15 or more, and n2 represents an integer of 0 to ^3. However, when n2 is 0, X ² is (It is a hydrocarbon group having 2 or 3 carbon atoms.)
R ¹ has the same meaning as R ¹ in the formula, the preferred range is also the same.
When X ² is a hydrocarbon group, it is preferably a hydrocarbon group having 1 to 3 carbon atoms, preferably a substituted or unsubstituted alkylene group having 1 to 3 carbon atoms, and an unsubstituted carbon number. It is more preferably an alkylene group of 1 to 3, more preferably an ethylene group. By employing such a hydrocarbon group, a photocurable composition having a lower viscosity and lower volatility can be obtained.
Y ² represents a substituent not having an aromatic group having a molecular weight of 15 or more, and the upper limit of the molecular weight of Y ² is preferably 80 or less. Y ² is an alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group, an isopropyl group, a tert-butyl group or a cyclohexyl group, a halogen atom such as a chloro group or a bromo group, a methoxy group, an ethoxy group, or a cyclohexyloxy group. Preferred examples include C1-C6 alkoxy groups such as a group.
n2 is preferably an integer of 0 to 2. When n2 is 1, the substituent Y is preferably in the para position. From the viewpoint of viscosity, when n2 is 2, X ² is preferably a single bond or a hydrocarbon group having 1 carbon atom.
The compound represented by the general formula (IV) is preferably a monofunctional (meth) acrylate having one (meth) acrylate group.

From the viewpoint of achieving both low viscosity and low volatility, the molecular weight of the (meth) acrylate compound represented by the general formula (IV) is preferably 175 to 250, and more preferably 185 to 245.
Moreover, it is preferable that the viscosity in 25 degreeC of the (meth) acrylate compound represented by general formula (IV) is 10 mPa * s or less, and it is more preferable that it is 6 mPa * s or less.
The compound represented by the general formula (IV) can be preferably used as a reaction diluent.

  The addition amount of the compound represented by the general formula (IV) in the photocurable composition is preferably 10% by mass or more from the viewpoint of the viscosity of the composition or the pattern accuracy after curing, and is 15% by mass or more. More preferably, it is particularly preferably 20% by mass or more. On the other hand, from the viewpoint of tackiness after curing and mechanical strength, the addition amount is preferably 95% by mass or less, more preferably 90% by mass or less, and particularly preferably 85% by mass or less.

Although the compound represented by general formula (IV) is illustrated below, it cannot be overemphasized that this invention is not limited to these.

Compound represented by general formula (V)
(In the general formula (V), R ¹ represents a hydrogen atom, an alkyl group or a halogen atom, X ³ is a single bond or a hydrocarbon group, and the hydrocarbon group contains a hetero atom in the chain. Y ³ represents a substituent having an aromatic group having a molecular weight of 15 or more, and n3 represents an integer of 1 to 3).
R ¹ has the same meaning as R ¹ in the formula, the preferred range is also the same.
X ¹ has the same meaning as Z ¹ described above, and the preferred range is also the same.
Y ³ represents a substituent having an aromatic group having a molecular weight of 15 or more. As the substituent having an aromatic group, the aromatic group is bonded to the aromatic ring of the general formula (V) through a single bond or a linking group. The aspect which is doing is preferable. Preferred examples of the linking group include an alkylene group, a linking group having a hetero atom (preferably —O—, —S—, —C (═O) O—, or a combination thereof), and an alkylene group or — A group consisting of O- and combinations thereof is more preferred. The substituent having an aromatic group having a molecular weight of 15 or more is preferably a substituent having a phenyl group. A mode in which the phenyl group is bonded through a single bond or the above linking group is preferable, and a phenyl group, a benzyl group, a phenoxy group, a benzyloxy group, and a phenylthio group are particularly preferable. The molecular weight of Y ³ is preferably 230 to 350.
n3 is preferably 1 or 2, more preferably 1.

  The amount of the compound represented by the general formula (V) in the composition is preferably 10% by mass or more, more preferably 20% by mass or more, and particularly preferably 30% by mass or more. On the other hand, from the viewpoint of tackiness after curing and mechanical strength, the addition amount is preferably 90% by mass or less, more preferably 80% by mass or less, and particularly preferably 70% by mass or less.

Although the compound represented by general formula (V) is illustrated below, it cannot be overemphasized that this invention is not limited to these.

Compound represented by general formula (VI)
(In General Formula (VI), X ⁶ is a (n6 + 1) -valent linking group, R ¹ is a hydrogen atom, an alkyl group, or a halogen atom. R ² and R ³ are each a substituent. There, n4 and n5 are each an integer of 0 to 4 .N6 is 1 or 2, X ⁴ and X ⁵ are each a hydrocarbon group, the hydrocarbon group in the chain (It may contain a linking group containing a hetero atom.)

X ⁶ represents an (n6 + 1) -valent linking group, preferably an alkylene group, —O—, —S—, —C (═O) O—, or a linking group in which a plurality of these are combined. is there. The alkylene group is preferably an alkylene group having 1 to 8 carbon atoms, more preferably an alkylene group having 1 to 3 carbon atoms. An unsubstituted alkylene group is preferred.
n6 is preferably 1. When n6 is 2, a plurality of R ¹ , X ⁵ , and R ² may be the same or different.
X ⁴ and X ⁵ are each preferably an alkylene group containing no linking group, more preferably an alkylene group having 1 to 5 carbon atoms, more preferably an alkylene group having 1 to 3 carbon atoms, A methylene group is preferred.
R ¹ has the same meaning as R ¹ in the formula, the preferred range is also the same.
R ² and R ³ each represent a substituent, preferably an alkyl group, a halogen atom, an alkoxy group, an acyl group, an acyloxy group, an alkoxycarbonyl group, a cyano group, or a nitro group. As an alkyl group, a C1-C8 alkyl group is preferable. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable. As an alkoxy group, a C1-C8 alkoxy group is preferable. As the acyl group, an acyl group having 1 to 8 carbon atoms is preferable. As the acyloxy group, an acyloxy group having 1 to 8 carbon atoms is preferable. As an alkoxycarbonyl group, a C1-C8 alkoxycarbonyl group is preferable.
n4 and n5 are each an integer of 0 to 4, when n4 or n5 is 2 or more, R ² and R ³ existing in plural numbers, respectively, may be the same or different.

The compound represented by the general formula (VI) is preferably a compound represented by the following general formula (VII).
(X ⁶ is an alkylene group, —O—, —S—, or a linking group in which a plurality of these are combined, and R ¹ is a hydrogen atom, an alkyl group, or a halogen atom, respectively.)
R ¹ has the same meaning as R ¹ in the formula, the preferred range is also the same.
When X < ⁶ > is an alkylene group, a C1-C8 alkylene group is preferable, More preferably, it is a C1-C3 alkylene group. An unsubstituted alkylene group is preferred.
The _{^{X 6, -CH 2 -, -}} CH 2 CH 2 -, - O -, - S- it is preferred.

  The content of the compound represented by the general formula (VI) in the photocurable composition used in the present invention is not particularly limited, but from the viewpoint of curability and composition viscosity, 1-100 mass% is preferable, 5-70 mass% is more preferable, 10-50 mass% is especially preferable.

Although the compound represented by general formula (VI) is illustrated below, it cannot be overemphasized that this invention is not limited to these. R ¹ in the following formula has the same meaning as R ¹ in the general formula (VI), and the preferred range is also the same, and particularly preferably a hydrogen atom.

(5) Polymerizable monomer group represented by the following general formula
(In the general formula, X ^{1 to} X ³ each independently represents a single bond or a linking group. Me represents a methyl group.)

When X < ¹ > -X < ³ > is a coupling group, Preferably it is an organic coupling group and it is preferable that it is a C1-C50 organic coupling group. Specific examples of the organic linking group include an oxyalkylene group, —O—C (═O) —, an alkylene group, and a group composed of a combination of two or more thereof. Examples of the oxyalkylene group include an ethylene oxide group and a propylene oxide group. Examples of the alkylene group include a propylene group, a butylene group, a pentyl group, and a hexyl group. X ^{1 to} X ³ are preferably single bonds.
The compound represented by the general formula is preferably liquid at 25 ° C., but may not be liquid.

Specific examples of the polymerizable monomer in the present invention are shown below.
m ¹ , m ² , m ³ , n ¹ , n ² , n ³ each represents an integer of 0 to 10, and the sum of m ¹ , m ² , m ³ , n ¹ , n ² and n ³ is It is a compound that is greater than 1 or a mixture of compounds that have an average of greater than 1.
l ¹ , l ² , and l ³ each represent an integer of 0 to 10, k ¹ , k ² , and k ³ each represent an integer of 3 to 6, and the sum of l ¹ , l ^2, and l ³ Is a compound greater than 1, or a mixture of compounds with an average of greater than 1.

(6) Polymerizable monomer group represented by the following general formula
[In the formula, Ar represents an arylene group which may have a substituent, X represents a single bond or an organic linking group, R ¹ represents a hydrogen atom or a methyl group, and n represents 2 or 3. ]

  In the general formula, the arylene group includes a hydrocarbon-based arylene group such as a phenylene group and a naphthylene group; a heteroarylene group in which indole, carbazole and the like are linked groups, preferably a hydrocarbon-based arylene group, More preferred is a phenylene group from the viewpoint of viscosity and etching resistance. The arylene group may have a substituent, and preferred examples of the substituent include an alkyl group, an alkoxy group, a hydroxyl group, a cyano group, an alkoxycarbonyl group, an amide group, and a sulfonamide group.

  Examples of the organic linking group for X include an alkylene group, an arylene group, and an aralkylene group, which may contain a hetero atom in the chain. Among these, an alkylene group and an oxyalkylene group are preferable, and an alkylene group is more preferable. X is particularly preferably a single bond or an alkylene group.

R ¹ is a hydrogen atom or a methyl group, preferably a hydrogen atom.

  n is 2 or 3, preferably 2.

  The polymerizable monomer is preferably a polymerizable monomer represented by the following general formula (Ia) or (Ib) from the viewpoint of reducing the composition viscosity.

Wherein, X ^1, X ² each independently represents a single bond or an alkylene group which may have a substituent having 1 to 3 carbon atoms, R ¹ represents a hydrogen atom or a methyl group. ]

In the general formula (Ia), X ¹ is preferably a single bond or a methylene group, and more preferably a methylene group from the viewpoint of viscosity reduction.
The preferable range of X ^{2 is the same as} the preferable range of X ¹ .
Wherein R ¹ is as in formula and R ¹ synonymous, and preferred ranges are also the same.

  When the polymerizable monomer is liquid at 25 ° C., it is preferable that the generation of foreign matters can be suppressed even when the addition amount is increased.

Specific examples of preferable polymerizable monomers are shown below. R ¹ is as in formula and R ¹ synonymous represents a hydrogen atom or a methyl group. The present invention is not limited to these specific examples.

(B) Photoinitiator The photocurable composition used for this invention contains a photoinitiator. As the photopolymerization initiator used in the present invention, any compound can be used as long as it is a compound that generates an active species capable of polymerizing the above polymerizable monomer by light irradiation. Examples of the photopolymerization initiator include a cationic polymerization initiator and a radical polymerization initiator, and a radical polymerization initiator is preferred. In the present invention, a plurality of photopolymerization initiators may be used in combination.

Content of the photoinitiator used for this invention is 0.01-15 mass% in all the compositions except a solvent, for example, Preferably it is 0.1-12 mass%, More preferably, it is 0. 2 to 7% by mass. When using 2 or more types of photoinitiators, the total amount becomes the said range.
When the content of the photopolymerization initiator is 0.01% by mass or more, the sensitivity (fast curability), resolution, line edge roughness, and coating strength tend to be improved, which is preferable. On the other hand, when the content of the photopolymerization initiator is 15% by mass or less, light transmittance, colorability, handleability and the like tend to be improved, which is preferable. In systems containing dyes and / or pigments, these may act as radical trapping agents, affecting photopolymerization and sensitivity. In consideration of this point, the amount of the photopolymerization initiator added is optimized in these applications.

  As the radical photopolymerization initiator used in the present invention, for example, a commercially available initiator can be used. As these examples, for example, those described in paragraph No. 0091 of JP-A No. 2008-105414 can be preferably used. Among these, acetophenone compounds, acylphosphine oxide compounds, and oxime ester compounds are preferred from the viewpoints of curing sensitivity and absorption characteristics.

Preferred examples of the acetophenone compound include hydroxyacetophenone compounds, dialkoxyacetophenone compounds, and aminoacetophenone compounds. Irgacure® 2959 (1- [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methyl-1-propan-1-one, preferably available from Ciba as the hydroxyacetophenone compound, Irgacure® 184 (1-hydroxycyclohexyl phenyl ketone), Irgacure® 500 (1-hydroxycyclohexyl phenyl ketone, benzophenone), Darocur® 1173 (2-hydroxy-2-methyl-1-phenyl) -1-propan-1-one).
The dialkoxyacetophenone compound is preferably Irgacure (registered trademark) 651 (2,2-dimethoxy-1,2-diphenylethane-1-one) available from Ciba.
As the aminoacetophenone compound, Irgacure (registered trademark) 369 (2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butanone-1), Irgacure (registered trademark) 379 (available from Ciba) is preferable. EG) (2-dimethylamino-2- (4methylbenzyl) -1- (4-morpholin-4-ylphenyl) butan-1-one, Irgacure® 907 (2-methyl-1 [4- Methylthiophenyl] -2-morpholinopropan-1-one.

As the acylphosphine oxide-based compound, preferably Irgacure (registered trademark) 819 (bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, Irgacure (registered trademark) 1800 (bis (2, 6-dimethoxybenzoyl) -2,4,4-trimethyl-pentylphosphine oxide, Lucirin TPO (2,4,6-trimethylbenzoyldiphenylphosphine oxide) available from BASF, Lucirin TPO-L (2,4,4) 6-trimethylbenzoylphenylethoxyphosphine oxide).
Irgacure (registered trademark) OXE01 (1,2-octanedione, 1- [4- (phenylthio) phenyl] -2- (O-benzoyloxime), Irgacure (registered trademark), preferably available from Ciba as an oxime ester compound Trademark) OXE02 (ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl]-, 1- (O-acetyloxime).
As the cationic photopolymerization initiator used in the present invention, sulfonium salt compounds, iodonium salt compounds, oxime sulfonate compounds and the like are preferable, and 4-methylphenyl [4- (1-methylethyl) phenyliodonium tetrakis (pentafluorophenyl) is preferable. Examples thereof include borate (PI2074 manufactured by Rhodea), 4-methylphenyl [4- (2-methylpropyl) phenyliodonium hexafluorophosphate (IRGACURE250 manufactured by Ciba), IRGACURE PAG103, 108, 121, 203 (manufactured by Ciba). .

(Other ingredients)
The photo-curable composition used in the present invention is not limited to the above-mentioned components, and other components such as a surfactant, an antioxidant, a solvent, and a polymer component are used in a range that does not impair the effects of the present invention. Ingredients may be included.
The photocurable composition used in the present invention may contain a colorant, a dye, a pigment, etc., but the effect of the present invention is more effectively exhibited if it does not contain it.

-Surfactant-
The photocurable composition used in the present invention preferably contains a surfactant.
The surfactant used in the present invention contains, for example, 0.001 to 5% by mass, preferably 0.002 to 4% by mass, and more preferably 0.005 to 3% by mass in the entire composition. It is. When using 2 or more types of surfactant, the total amount becomes the said range. If the surfactant is less than 0.001 in the composition, the effect of coating uniformity is insufficient. On the other hand, if it exceeds 5% by mass, the mold transfer characteristics are deteriorated, which is not preferable.
The surfactant preferably contains at least one of a fluorine-based surfactant, a silicone-based surfactant, and a fluorine / silicone-based surfactant. Both the fluorine-based surfactant and the silicone-based surfactant or fluorine -More preferably, a silicone-based surfactant is included, and most preferably, a fluorine-silicone-based surfactant is included.
Here, the fluorine / silicone surfactant refers to one having both requirements of a fluorine surfactant and a silicone surfactant.
By using such a surfactant, the composition of the present invention can be applied to a silicon wafer for manufacturing semiconductor devices, a glass square substrate for manufacturing liquid crystal devices, a chromium film, a molybdenum film, a molybdenum alloy film, a tantalum film, and tantalum. Striations and scale-like patterns (such as alloy films, silicon nitride films, amorphous silicone films, tin oxide-doped indium oxide (ITO) films, tin oxide films, etc.) The purpose is to solve the problem of poor coating such as uneven drying of the resist film), and the fluidity of the composition into the cavity of the mold recess is improved, the peelability between the mold and the resist is improved, and between the resist and the substrate It becomes possible to improve the adhesion and to lower the viscosity of the composition. In particular, in the composition of the present invention, the coating uniformity can be greatly improved by adding the above-mentioned surfactant, and in coating using a spin coater or slit scan coater, good coating suitability can be obtained regardless of the substrate size. can get.

Examples of the nonionic fluorosurfactant used in the present invention include trade names Florard FC-430 and FC-431 (Sumitomo 3M), trade names Surflon “S-382” (Asahi Glass Co., Ltd.), EFTOP “ EF-122A, 122B, 122C, EF-121, EF-126, EF-127, MF-100 "(manufactured by Tochem Products), trade names PF-636, PF-6320, PF-656, PF-6520 ( All are OMNOVA), brand names FT250, FT251, DFX18 (all manufactured by Neos Co., Ltd.), brand names Unidyne DS-401, DS-403, DS-451 (all manufactured by Daikin Industries, Ltd.) ), Trade name Megafuk 171, 172, 173, 178K, 178A (all manufactured by Dainippon Ink & Chemicals, Inc.). Examples of nonionic silicon-based surfactants include trade name SI-10 series (manufactured by Takemoto Yushi Co., Ltd.), mega-fac 31 (manufactured by Dainippon Ink & Chemicals), and KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.). Can be mentioned.
Examples of fluorine / silicone surfactants used in the present invention include trade names X-70-090, X-70-091, X-70-092, X-70-093 (all Shin-Etsu Chemical Co., Ltd.). Manufactured), and trade names Megafuk R-08 and XRB-4 (all manufactured by Dainippon Ink & Chemicals, Inc.).

-Antioxidant-
Further, the photocurable composition used in the present invention preferably contains a known antioxidant. By including an antioxidant, transparency can be improved. The antioxidant used for this invention contains 0.01-10 mass% in all the compositions, for example, Preferably it is 0.2-5 mass%. When using 2 or more types of antioxidant, the total amount becomes the said range.
The antioxidant suppresses fading caused by heat or light irradiation and fading caused by various oxidizing gases such as ozone, active oxygen, NO _x , SO _x (X is an integer). In particular, in the present invention, the addition of an antioxidant has an advantage that the cured film can be prevented from being colored, or the film thickness reduction due to decomposition can be reduced. Examples of such antioxidants include hydrazides, hindered amine antioxidants, nitrogen-containing heterocyclic mercapto compounds, thioether antioxidants, hindered phenol antioxidants, ascorbic acids, zinc sulfate, thiocyanates, Examples include thiourea derivatives, sugars, nitrites, sulfites, thiosulfates, hydroxylamine derivatives, and the like. Among these, hindered phenol antioxidants and thioether antioxidants are particularly preferable from the viewpoint of coloring the cured film and reducing the film thickness.

  As commercially available products of antioxidants, Irganox 1010, 1035, 1076, 1222 (manufactured by Ciba Geigy Co., Ltd.), Antigene P, 3C, FR, Sumilyzer S, Sumilyzer GA80 (manufactured by Sumitomo Chemical), Adeka Stub AO70, AO80, AO503 (made by ADEKA Co., Ltd.) etc. are mentioned, These may be used independently and may be used in mixture.

-Polymerization inhibitor-
Furthermore, the photocurable composition used in the present invention preferably contains a polymerization inhibitor. As content of a polymerization inhibitor, it is 0.001-1 mass% with respect to all the polymerizable monomers, More preferably, it is 0.005-0.5 mass%, More preferably, it is 0.008-0. By blending an appropriate amount of a polymerization inhibitor of 05% by mass, it is possible to suppress a change in viscosity over time while maintaining high curing sensitivity. The polymerization inhibitor may be added during the production of the polymerizable monomer, or may be added later to the photocurable composition.

  Furthermore, it is preferable that the photocurable composition in the present invention removes a polymer impurity containing a polymerizable monomer as a repeating unit. For the removal method and the like, the description in the maintenance liquid can be referred to.

After the precipitated polymer is removed, the polymer is blended into the photocurable composition by a solution as it is or by a method such as concentration or solvent replacement. In the present invention, when producing a polymerizable monomer, it is preferable to add a polymerization inhibitor, and it is preferable to add it at a stage prior to the concentration step.
As a polymerization inhibitor, hydroquinone, p-methoxyphenol, di-tert-butyl-p-cresol, pyrogallol, tert-butylcatechol, benzoquinone, 4,4′-thiobis (3-methyl-6-tert-butylphenol), 2,2′-methylenebis (4-methyl-6-tert-butylphenol), N-nitrosophenylhydroxyamine primary cerium salt, phenothiazine, phenoxazine, 4-methoxynaphthol, 2,2,6,6-tetramethylpiperidine -1-oxyl free radical, 2,2,6,6-tetramethylpiperidine, 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl free radical, nitrobenzene, dimethylaniline and the like, Preferably p-benzoquinone, 2, , 6,6-tetramethyl-1-oxyl free radical, 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl free radical, phenothiazine. These polymerization inhibitors suppress the generation of polymer impurities not only during the production of the polymerizable monomer but also during the storage of the photocurable composition, and suppress the deterioration of pattern formation during imprinting.

Below, the pattern formation method (pattern transfer method) using a photocurable composition is described concretely.
In the pattern forming method, first, a photocurable composition is placed on a substrate or a mold having a fine pattern by ink jetting to form a pattern forming layer. The droplets placed by inkjet discharge may be placed at intervals, or may be placed so that the droplets are coupled to each other. The amount of droplets is preferably about 1 pl to 20 pl. The total amount of droplets varies depending on the pattern to be formed, and is adjusted so that the pattern and the remaining film have an appropriate thickness. Further, it is preferable to make the interval between the droplets non-uniform according to the density of the pattern.
Regarding other conditions, the description of paragraph numbers 0103 to 0115 in JP 2010-109092 A can be referred to.

The pattern formed by the pattern forming method of the present invention is also useful as an etching resist. When the photocurable composition used in the present invention is used as an etching resist, first, a silicon wafer or the like on which a thin film such as SiO ₂ is formed is used as a base material, and nano pattern is formed on the base material by a pattern forming method. A fine pattern of order is formed. Thereafter, a desired pattern can be formed on the substrate by etching using an etching gas such as hydrogen fluoride in the case of wet etching or CF _{4 in} the case of dry etching. The photocurable composition used in the present invention preferably has good etching resistance against dry etching using fluorocarbon or the like.

  The present invention will be described more specifically with reference to the following examples. The materials, amounts used, ratios, processing details, processing procedures, and the like shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below.

(Maintenance liquid adjustment)
The maintenance liquid was blended by blending the compounds shown below in the proportions shown in Table 3 below. The polymerizable monomers (X4) to (X6) used for the maintenance liquid and the polymerizable monomers (M1) to (M6) used for the curable composition were dissolved in methanol, and then the pore size was 0.1 μm. The polymer component was removed by filtration using a tetrafluoroethylene filter and concentrated. When these polymerizable monomers were subjected to GPC measurement under the following conditions, no polymer component was observed.
(GPC conditions)
A 2695 separation module manufactured by Waters was used, and a column made by connecting three KF-805 manufactured by Shodex was used. Tetrahydrofuran was used as the eluent, and the flow rate was 1 mL / min at 40 ° C. The detector is an RI detector (WATERS, 2414) or a multi-angle light scattering detector (Wyatt Technology, DAWN-EOS) as a laser light scattering detector and an immediate digital correlator (WyattQels) connected to the 90-degree scattered light. Was observed.

  The viscosity was measured at 25 ± 0.2 ° C. using a RE-80L rotational viscometer manufactured by Toki Sangyo Co., Ltd.

(Preparation of photocurable composition)
A polymerizable monomer, a photopolymerization initiator, and a surfactant described below were blended in a weight ratio as shown in the table so that the total amount was 100% by mass to prepare a photocurable composition.

<Polymerizable monomer>
M1: Hexanediol diacrylate: manufactured by Osaka Organic Chemical Company, V # 230
M2: Phenoxyethyl acrylate: Osaka Organic Chemical Company, V # 192
M3: 1,3-bis (acryloxymethyl) benzene: synthesized from α, α′-dichloro-m-xylene and acrylic acid M4: isobornyl acrylate: IBXA manufactured by Osaka Organic Chemical Co., Ltd.
M5: Tricyclodecane dimethanol diacrylate: Shin Nakamura Chemical Co., Ltd., NK ester A-DCP
M6: perfluorohexyl ethyl acrylate: manufactured by Kanto Chemical Co., Inc.

<Photopolymerization initiator>
P1: IRGACURE-379EG (Ciba Specialty Chemicals)
P2: IRGACURE-OXE01 (Ciba Specialty Chemicals)

<Surfactant>
W1: Fluorosurfactant (manufactured by OMNOVA: PF-656)
W2: Silicone surfactant (manufactured by Dainippon Ink and Chemicals, Inc .: MegaFuck 31)

<Pattern formability evaluation>
According to the following method, pattern formation was performed with a combination of the maintenance liquid and the photocurable composition shown in the following table, and pattern formability evaluation was performed. In this experiment, an inkjet head SX3 manufactured by Fuji Film Dimatics was used.

  The ink-jet head was replaced with the photocurable composition from the state filled with the maintenance liquid, and the photocurable composition was filled. After cleaning the nozzle surface with the maintenance liquid, the photocurable composition was ejected onto the silicon wafer so as to have a predetermined pitch using an inkjet head. Specifically, the following method was used.

(Filling with maintenance liquid)
In the flow path configuration shown in FIG. 1, first, the pressure controller was set to a pressure of 30 kPa, and the maintenance liquid was supplied to the inkjet head. At this time, the valve on the OUT side of the ink jet head was opened to sufficiently discharge bubbles in the head. When the bubbles were not discharged from the OUT side, the pressure of the pressure controller was set to 0 kPa and the OUT side valve was closed. Further, the pressure of the pressure controller was set to 10 kPa, and the maintenance liquid was discharged from the nozzle. After confirming the discharge from all nozzles, the pressure was set to -0.75 kPa.
As the pressure controller, PC71 manufactured by Nagano Keiki Co., Ltd. was used. Further, a deaeration module EF-G3 manufactured by DIC Corporation was disposed between the head, the maintenance liquid tank, and the photocurable composition tank in order to prevent bubbles from entering the head.
In FIG. 1, 1 is a photocurable composition side pressure controller, 2 is a maintenance liquid side controller, 3 to 6 are filters, 7 is a photocurable composition tank, and 8 is a maintenance liquid tank. 9 is a three-way valve, 10 is an air bubble remover, 11 is a waste liquid tank, 12 is a degassing module, 13 is an inkjet head, 14 is an ink receiver, 15 is a valve, 16 is a waste liquid tank, Each is shown.

(Filling with photocurable composition)
Next, the three-way valve was switched, and the pressure controller connected to the tank in which the photocurable composition was stored was operated to supply the photocurable composition to the inkjet head. The valve on the OUT side of the inkjet head was opened, and the pressure controller was operated at 30 kPa. When air bubbles entered between the maintenance liquid and the photocurable composition, the three-way valve for removing air bubbles was switched so that the air bubbles did not enter the head. The three-way valve was switched so that the photocurable composition could be supplied to the head with no bubbles.
The photo-curable composition was washed away so that the maintenance liquid was sufficiently discharged from the head OUT side.
Here, 200 ml was washed away. Thereafter, the pressure of the pressure controller was set to 0 kPa, the OUT side valve was closed, the pressure of the pressure controller was set to 10 kPa, and the maintenance liquid and the photocurable composition were discharged from the nozzle. After discharging a sufficient amount of the maintenance liquid in the head (20 ml), the discharge from all nozzles was confirmed, and the pressure was set to -0.75 kPa.

(Nozzle surface cleaning)
Cleaning of the nozzles of the inkjet head used in this example was performed as follows.
Nozzle cleaning was performed using the maintenance mechanism shown in FIG. The ink jet head 21 was lowered downward so that the nozzle surface 20 could come into contact with the maintenance liquid of the wiping unit 29 and the coating unit 27, and the ink jet head 21 was moved in the direction of the arrow in the figure (see FIG. 2B). At this time, the application roller 25 rolled up the maintenance liquid 28 stored in the maintenance liquid tray 26 while rotating in the same direction as the movement direction of the head unit 21 to form a maintenance liquid film on the outer surface. Further, the unwinding unit 31 and the winding unit 33 are driven so that the wiping sheet 36 moves in the direction opposite to the moving direction of the head 21.
The nozzle surface 20 of the inkjet head 21 reaches the upper part of the application roller 25 while moving in the direction of the arrow in FIG. 2A, contacts the maintenance liquid 28 on the surface of the application roller 25, and the maintenance liquid 28 is applied. It was. Then, it was further moved in a state where the maintenance liquid 28 was applied. At this time, if a photocurable composition or the like is attached to the nozzle surface 20, it is dissolved by the maintenance liquid 28. And it reaches on the wiping roller part 93. At this position, the wiping sheet 36 was pressed against the nozzle surface 20, and the deposit B dissolved by the maintenance liquid 28 was wiped off by the wiping sheet 36 (see FIG. 2C). The application of the maintenance liquid 28 by the application roller 25 and the wiping by the wiping sheet 36 were continuously performed, and the deposit B on the entire nozzle surface 20 was wiped (see FIG. 2D).
The diameter of the coating roll was 40 mm, the number of rotations of the coating roll was 600 rpm, a 0.5 mm maintenance liquid film was formed on the coating roll, the head moving speed was 80 mm / sec, and the maintenance liquid was applied to the nozzle surface. . Toraysee (Toray) was used as the wiping sheet and moved at 1.5 mm / sec in the direction opposite to the head to wipe the nozzle surface.
In FIG. 2, B is a photocurable composition, 20 is a nozzle surface, 21 is an inkjet head, 22 is a maintenance unit, 23 is a waste liquid tray, 24 is a delivery path, and 25 is a coating roller. 26 is a tray, 27 is a coating unit, 28 is maintenance liquid, 29 is a wiping unit, 30 is a wiping sheet, 31 is an unwinding section, 32 is a wiping roller section, 33 is a winding section. , 34 is a housing, 35 is a vertical movement mechanism, 35A is a moving table, and 36 is a transport roller.

(Dropping of photocurable composition)
Using the inkjet head after the nozzle surface cleaning, the photocurable composition on the silicon wafer was ejected.
After confirming the discharge of all nozzles, the photocurable composition was controlled by controlling the discharge timing so that the head was scanned in the X direction with a droplet amount of 8 pl per nozzle and at intervals of 450 μm on the silicon wafer. Discharged. This was carried out by rotating the head so that the pitch was 450 μm in the direction perpendicular to the X direction. Since the nozzles of the inkjet head SX3 used here have a pitch of 508 um, the nozzle alignment direction and the X direction were rotated 62.4 ° from the parallel state. This image is shown in FIG.

(Pattern formation)
A mold release treatment was performed with a silane coupling agent (Daikin Co., Ltd., OPTOOL DSX) having a 25 nm line / space 1/1, a groove depth of 50 nm, and a surface having a perfluoropolyether structure. The mold was placed and cured with a mercury lamp light containing 365 nm light while pressing the mold against the composition at a pressure of 1 MPa under a nitrogen stream at an exposure illuminance of 10 mW / cm ² and an exposure dose of 200 mJ / cm ^2. Then, the mold was slowly peeled off. The obtained pattern is observed with a scanning microscope. (I) A huge pattern defect in which pattern transfer is not possible over a diameter of 1 μm or more, and (II) a pattern such as a chipped, fallen or peeled pattern. Defects were evaluated as follows.

(I) Huge pattern defect a with no pattern transfer over a diameter of 1 μm or more a: Huge pattern defect was not seen at all b: Huge pattern defect was found slightly.
c: Many huge pattern defects were observed.
(II) Minute pattern defects such as pattern chipping, falling down, peeling, etc. A: No pattern defects were observed at all.
B: A pattern defect was slightly observed.
C: Many pattern defects were observed.

  It was found that when an ink jet device maintained using the maintenance liquid of the present invention was used, the pattern forming property was high. It is quite surprising that the type of maintenance liquid affects imprintability.

DESCRIPTION OF SYMBOLS 1 Photocurable composition side pressure controller 2 Maintenance liquid side controller 3 Filter 4 Filter 5 Filter 6 Filter 7 Photocurable composition tank 8 Maintenance liquid tank 9 Three-way valve 10 Bubble removal 11 Waste liquid tank 12 Deaeration module 13 Inkjet Head 14 Ink receptacle 15 Valve 16 Waste liquid tank 20 Nozzle surface 21 Inkjet head 22 Maintenance section 23 Waste liquid tray 24 Delivery path 25 Application roller 26 Tray 27 Application unit 28 Maintenance liquid 29 Wiping unit 30 Wiping sheet 31 Unwinding section 32 Wiping roller section 33 Winding unit 34 Housing 35 Vertical movement mechanism 35A Moving table 36 Conveying roller

Claims (13)

The photo-curable composition for imprints mainly containing polymerizable monomer, on the mold having a substrate on or fine patterns, ejected using an ink jet device, the light-curable composition for imprints A maintenance liquid for an inkjet device used in a pattern forming method including light irradiation in a state sandwiched between a substrate and a mold having a fine pattern,
The maintenance liquid contains a polymerizable monomer having an ester and / or ether functional group, and the polymerizable monomer having an ester and / or ether functional group further contains an aromatic group and / or an alicyclic hydrocarbon. Having a group,
At least one polymerizable monomer contained in the maintenance liquid is in common with at least one polymerizable monomer contained in the curable composition for photoimprint,
Maintenance liquid. The maintenance liquid according to claim 1 , wherein the curable composition for photoimprint contains (meth) acrylate. The maintenance liquid according to claim 1 or 2 , comprising at least one kind of (meth) acrylate having an aromatic group and / or an alicyclic hydrocarbon group contained in the curable composition for photoimprint. The maintenance liquid according to any one of claims 1 to 3 , wherein 99% by mass or more of the polymerizable monomer contained in the curable composition for photoimprint is (meth) acrylate. The maintenance liquid according to any one of claims 1 to 4 , wherein the viscosity of the maintenance liquid at 25 ° C is 50 mPa · s or less. The maintenance liquid according to any one of claims 1 to 5 , wherein the maintenance liquid has a boiling point at 1 atm of 150 ° C or higher. The maintenance liquid according to any one of claims 1 to 6 , wherein the maintenance liquid contains 50% by mass or more of a compound having an ester and / or ether functional group. The maintenance liquid according to any one of claims 1 to 7, wherein the polymerizable monomer contained in the photoimprint curable composition and the polymerizable monomer contained in the maintenance liquid are the same. When the maintenance liquid is measured using a laser light scattering detector in gel permeation chromatography measurement, a component derived from a polymerizable monomer having a molecular weight larger than the polymerizable monomer contained in the maintenance liquid is not detected, The maintenance liquid according to any one of claims 1 to 8. The maintenance liquid according to any one of claims 1 to 7 and 9,
A curable composition for photoimprints containing (meth) acrylates having ester and / or ether functional groups;
A kit having The kit according to claim 10, wherein the (meth) acrylate contained in the curable composition for photoimprints has an aromatic group and / or an alicyclic hydrocarbon group. The kit according to claim 10 or 11, wherein 99% by mass or more of the polymerizable monomer contained in the curable composition for photoimprint is (meth) acrylate. The kit according to any one of claims 10 to 12, wherein the polymerizable monomer contained in the photo-imprinting curable composition and the polymerizable monomer contained in the maintenance liquid are the same.