WO2024111393A1

WO2024111393A1 - Curable composition, method for producing cured article, film, optical element, image sensor, solid-state imaging element, image display device, and radical polymerization initiator

Info

Publication number: WO2024111393A1
Application number: PCT/JP2023/039908
Authority: WO
Inventors: 雅臣牧野; 賢鮫島; 英知古山
Original assignee: 富士フイルム株式会社
Priority date: 2022-11-21
Filing date: 2023-11-06
Publication date: 2024-05-30

Abstract

Provided are: a curable composition comprising a radical polymerization initiator that has a group having an indole backbone, a group formed by condensing at least three rings different from the indole backbone and a (ket)oxime ester group and a radical curable compound, in which the group formed by condensing at least three rings and the (ket)oxime ester group are bound to the group having the indole backbone; a method for producing a cured article; a film; an optical element; an image sensor; a solid-state imaging element; an image display device; and a radical polymerization initiator.

Description

CURABLE COMPOSITION, PROCESS FOR PRODUCING CURED PRODUCT, FILM, OPTICAL ELEMENT, IMAGE SENSOR, SOLID-STATE IMAGING DEVICE, IMAGE DISPLAY DEVICE, AND RADICAL POLYMERIZATION INITIATOR

The present disclosure relates to a curable composition, a method for producing a cured product, a film, an optical element, an image sensor, a solid-state imaging element, an image display device, and a radical polymerization initiator.

2. Description of the Related Art Optical filters such as color filters are produced using a curable composition that contains a colorant, a photopolymerization initiator, and a curable compound.
As a conventional curable composition, the composition described in Patent Document 1 is known.
Patent Document 1 describes a composition containing a photopolymerization initiator having an indole skeleton.

Patent document 1: International Publication No. 2015/152153

An object of the present disclosure is to provide a curable composition that is excellent in sensitivity and adhesion to a substrate.
Another problem to be solved by another embodiment of the present disclosure is to provide a method for producing a cured product, a film, an optical element, an image sensor, a solid-state imaging element, or an image display device using the curable composition.
Furthermore, a problem to be solved by another embodiment of the present disclosure is to provide a novel radical polymerization initiator.

Means for solving the above problems include the following aspects.
<1> A radical polymerization initiator having a group having an indole skeleton, a group having three or more condensed rings different from the indole skeleton, and a (keto)oxime ester group;
A radical curable compound;
Including,
A curable composition, wherein the group having three or more condensed rings and the (keto)oxime ester group are bonded to the group having an indole skeleton.
<2> The curable composition according to <1> above, wherein the radical polymerization initiator is a compound represented by the following formula (1):

In formula (1),
_Z1 represents any one of an alkyl group, an aryl group, a heteroaryl group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, a hydroxyl group, a carboxyl group, a cyano group, a nitro group, a halogen atom, and an acyl group;
X represents a group having three or more condensed rings;
L represents a single bond or a divalent organic group;
R ₁₅ to R ₁₉ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a nitro group, an alkoxy group, or an aryloxy group, two or more of R ¹⁵ to R ¹⁹ may be bonded to each other to form a ring structure, and the ring structure thus formed may be an aromatic ring;
Y ₁ represents a hydrogen atom, an alkyl group or an aryl group;
R ₁ represents an alkyl group, an aryl group, a heteroaryl group, an alkoxy group, an aryloxy group, or a heteroaryloxy group;
m and n each independently represent 0 or 1.
<3> The curable composition according to <1> or <2> above, wherein the radical polymerization initiator is a compound represented by the following formula (2):

In formula (2),
Ar ₁ represents an alkyl group, an aryl group, or a heteroaryl group;
_Ar2 represents a divalent organic group;
_X11 and _X12 each independently represent a single bond, O, S, NR, _CRxRy _, or C=O, and R, _Rx , and _Ry each independently represent a hydrogen atom, an alkyl group, or an aryl group;
R ₁₁ and R ₁₂ each independently represent an alkyl group, an aryl group, a halogen atom, a nitro group, a hydroxyl group, an alkoxy group, an aryloxy group, an alkylthio group, or an arylthio group;
R ₁₅ to R ₁₉ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a nitro group, an alkoxy group, or an aryloxy group, two or more of R ¹⁵ to R ¹⁹ may be bonded to each other to form a ring structure, and the ring structure thus formed may be an aromatic ring;
Y ₁ represents a hydrogen atom, an alkyl group or an aryl group;
R ₁ represents an alkyl group, an aryl group, a heteroaryl group, an alkoxy group, an aryloxy group, or a heteroaryloxy group;
m and n each independently represent 0 or 1;
p and q each independently represent an integer of 0 to 3.
<4> The curable composition according to the above <2> or <3>, wherein Y ₁ is a group represented by the following formula (3):

In formula (3),
_R2 represents an alkyl group, provided that when _L2 is CHR, _R2 may be a hydrogen atom;
_R3 represents a hydrogen atom or an alkyl group;
_R4 represents an alkyl group;
_L1 and _L2 each independently represent CHR, O, S, or NR, and each R independently represents a hydrogen atom or an alkyl group;
Two or more of R ₂ , R ₃ , R ₄ and R may be bonded to each other to form a ring structure;
_Z2 represents a single bond or an alkylene group having 1 to 6 carbon atoms;
* indicates the linkage to the oxime group.
<5> The curable composition according to any one of <2> to <4>, wherein Y ₁ is a group represented by the following formula (4):

In formula (4),
_L3 and _L4 each independently represent CHR, O, S, or NR, and at least one of _L3 and _L4 is CHR, in which R represents a hydrogen atom or an alkyl group;
Each _R5 independently represents a hydrogen atom or an alkyl group;
r represents an integer from 1 to 6;
* indicates the linkage to the oxime group.
<6> The curable composition according to any one of the above <3> to <5>, wherein Ar ₁ is an aryl group or a heteroaryl group.
<7> The curable composition according to any one of the above <3> to <6>, wherein Ar ₂ is an arylene group.
<8> The curable composition according to any one of <2> to <7>, wherein the m is 1.
<9> The curable composition according to any one of the above <1> to <8>, further comprising a colorant.
<10> The curable composition according to any one of <1> to <9> above, further comprising a thiol-based chain transfer agent.
<11> A method for producing a curable composition according to any one of <1> to <10> above, comprising the step of irradiating the curable composition with an excimer laser beam having a wavelength of 150 nm to 300 nm.
A method for producing a cured product.
<12> A film obtained by curing the curable composition according to any one of <1> to <10> above.
<13> An optical element comprising the film according to <12> above.
<14> An image sensor comprising the film according to <12> above.
<15> A solid-state imaging device comprising the film according to <12> above.
<16> An image display device comprising the film according to <12> above.
<17> A radical polymerization initiator represented by the following formula (2):

In formula (2),
Ar ₁ represents an alkyl group, an aryl group, or a heteroaryl group;
_Ar2 represents a divalent organic group;
_X11 and _X12 each independently represent a single bond, O, S, NR, _CRxRy _, or C=O, and R, _Rx , and _Ry each independently represent a hydrogen atom, an alkyl group, or an aryl group;
R ₁₁ and R ₁₂ each independently represent an alkyl group, an aryl group, a halogen atom, a nitro group, a hydroxyl group, an alkoxy group, an aryloxy group, an alkylthio group, or an arylthio group;
R ₁₅ to R ₁₉ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a nitro group, an alkoxy group, or an aryloxy group, two or more of R ¹⁵ to R ¹⁹ may be bonded to each other to form a ring structure, and the ring structure thus formed may be an aromatic ring;
Y ₁ represents a hydrogen atom, an alkyl group or an aryl group;
R ₁ represents an alkyl group, an aryl group, a heteroaryl group, an alkoxy group, an aryloxy group, or a heteroaryloxy group;
m and n each independently represent 0 or 1;
p and q each independently represent an integer of 0 to 3.

According to an embodiment of the present disclosure, a curable composition having excellent sensitivity and adhesion to a substrate is provided.
Further, according to other embodiments of the present disclosure, there are provided a method for producing a cured product, a film, an optical element, an image sensor, a solid-state imaging element, or an image display device using the curable composition.
Furthermore, according to another embodiment of the present disclosure, a novel radical polymerization initiator is provided.

The contents of the present disclosure will be described in detail below. The following description of the components may be based on a representative embodiment of the present disclosure, but the present disclosure is not limited to such an embodiment.
In this specification, the word "to" is used to mean that the numerical values before and after it are included as the lower limit and upper limit.
In the description of groups (atomic groups) in this specification, when there is no indication of whether they are substituted or unsubstituted, the term encompasses both unsubstituted groups (atomic groups) and substituted groups (atomic groups). For example, an "alkyl group" encompasses not only alkyl groups without a substituent (unsubstituted alkyl groups) but also alkyl groups with a substituent (substituted alkyl groups).
In the present disclosure, the term "(keto)oxime ester group" refers to both or either of a ketoxime ester group and an oxime ester group.
In this specification, unless otherwise specified, the term "exposure" includes not only exposure using light but also drawing using particle beams such as electron beams and ion beams. Examples of light used for exposure include the bright line spectrum of a mercury lamp, far ultraviolet light represented by an excimer laser, extreme ultraviolet light (EUV light), X-rays, active rays or radiation such as electron beams.
In this specification, "(meth)acrylate" refers to both or either of acrylate and methacrylate, "(meth)acrylic" refers to both or either of acrylic and methacrylic, and "(meth)acryloyl" refers to both or either of acryloyl and methacryloyl.
In this specification, the weight average molecular weight and number average molecular weight are values calculated in terms of polystyrene measured by GPC (gel permeation chromatography).
In this specification, the total solids content refers to the total mass of all components of the composition excluding the solvent.
In this specification, a pigment means a colorant that is poorly soluble in a solvent.
In this specification, the term "process" refers not only to an independent process, but also to a process that cannot be clearly distinguished from other processes, as long as the intended effect of the process is achieved.
In the present specification, for oxime compounds having E- and Z-stereoisomers, unless otherwise specified, either the E- or Z-isomer may be used.
The present disclosure will be described in detail below.

(Curable Composition)
The curable composition according to the present disclosure comprises: a radical polymerization initiator having a group having an indole skeleton, a group having three or more condensed rings different from the indole skeleton, and a (keto)oxime ester group; and a radical curable compound, wherein the group having three or more condensed rings and the (keto)oxime ester group are bonded to the group having an indole skeleton.
In addition, the curable composition according to the present disclosure can be suitably used as a curable composition for exposure to light having a wavelength of 150 nm to 300 nm, and can be more suitably used as a curable composition for exposure to an excimer laser having a wavelength of 150 nm to 300 nm.

As a result of extensive investigations, the present inventors have found that the sensitivity and adhesion to a substrate of the curable composition are improved by employing the above-mentioned configuration.
When the radical polymerization initiator has a group having an indole skeleton and a group having three or more condensed rings, the light absorption efficiency is improved.
Furthermore, the radical polymerization initiator has a (keto)oxime ester group, which improves the light absorption efficiency and promotes the generation of radicals from the (keto)oxime ester group.
It is presumed that these factors enable the production of a curable composition that has high sensitivity and excellent adhesion to substrates.

The curable composition according to the present disclosure is preferably used as a curable composition for optical filters. Examples of optical filters include color filters and infrared transmission filters, and color filters are preferred. That is, the curable composition according to the present disclosure is preferably used as a curable composition for color filters. More specifically, it can be preferably used as a curable composition for forming pixels of a color filter. Examples of types of pixels include red pixels, green pixels, blue pixels, magenta pixels, cyan pixels, and yellow pixels.

Preferred examples of the infrared transmission filter include filters that satisfy the spectral characteristics of a maximum transmittance of 20% or less (preferably 15% or less, more preferably 10% or less) in the wavelength range of 400 nm to 640 nm and a minimum transmittance of 70% or more (preferably 75% or more, more preferably 80% or more) in the wavelength range of 1,100 nm to 1,300 nm. The infrared transmission filter is preferably a filter that satisfies any of the following spectral characteristics (1) to (5).
(1): A filter having a maximum transmittance of 20% or less (preferably 15% or less, more preferably 10% or less) in the wavelength range of 400 nm to 640 nm, and a minimum transmittance of 70% or more (preferably 75% or more, more preferably 80% or more) in the wavelength range of 800 nm to 1,500 nm.
(2): A filter having a maximum transmittance of 20% or less (preferably 15% or less, more preferably 10% or less) in the wavelength range of 400 nm to 750 nm, and a minimum transmittance of 70% or more (preferably 75% or more, more preferably 80% or more) in the wavelength range of 900 nm to 1,500 nm.
(3): A filter having a maximum transmittance of 20% or less (preferably 15% or less, more preferably 10% or less) in the wavelength range of 400 nm to 830 nm, and a minimum transmittance of 70% or more (preferably 75% or more, more preferably 80% or more) in the wavelength range of 1,000 nm to 1,500 nm.
(4): A filter having a maximum transmittance of 20% or less (preferably 15% or less, more preferably 10% or less) in the wavelength range of 400 nm to 950 nm, and a minimum transmittance of 70% or more (preferably 75% or more, more preferably 80% or more) in the wavelength range of 1,100 nm to 1,500 nm.
(5): A filter having a maximum transmittance of 20% or less (preferably 15% or less, more preferably 10% or less) in the wavelength range of 400 nm to 1,050 nm, and a minimum transmittance of 70% or more (preferably 75% or more, more preferably 80% or more) in the wavelength range of 1,200 nm to 1,500 nm.

The curable composition according to the present disclosure is preferably used for solid-state imaging devices. More specifically, it is preferably used as a curable composition for optical filters used in solid-state imaging devices, and is more preferably used as a curable composition for color filters used in solid-state imaging devices.

The solids concentration of the curable composition according to the present disclosure is preferably 5% by mass to 40% by mass. The lower limit is more preferably 7.5% by mass or more, and even more preferably 10% by mass or more. The upper limit is more preferably 35% by mass or less, and even more preferably 30% by mass or less.

<Radical Polymerization Initiator>
The curable composition according to the present disclosure contains a radical polymerization initiator (hereinafter also referred to as a "specific radical polymerization initiator") which has a group having an indole skeleton, a group having three or more condensed rings different from the indole skeleton, and a (keto)oxime ester group, wherein the group having three or more condensed rings and the (keto)oxime ester group are bonded to the group having an indole skeleton.
The specific radical polymerization initiator is preferably a photoradical polymerization initiator, and more preferably a photoradical polymerization initiator that generates radicals when exposed to light having a wavelength of 150 nm to 300 nm.
The exposure wavelength at which the specific radical polymerization initiator generates radicals is preferably 150 nm to 460 nm, more preferably 150 nm to 420 nm, further preferably 150 nm to 380 nm, and particularly preferably 150 nm to 300 nm.

- Group having an indole skeleton -
The group having an indole skeleton is not particularly limited as long as it has an indole structure.
In one embodiment, the group having an indole skeleton is preferably a group represented by the following formula (5). In formula (5), * represents the bonding position between the group having three or more condensed rings and the (keto)oxime ester group. Note that * may be bonded to the group having three or more condensed rings and the (keto)oxime ester group via a divalent organic group or the like.

In formula (5), R ₁₅ to R ₁₉ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a nitro group, an alkoxy group, or an aryloxy group, and two or more of R ¹⁵ to R ¹⁹ may be linked to each other to form a ring structure, and the formed ring structure may be an aromatic ring.
Examples of halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms. The alkyl group is preferably an alkyl group having 1 to 12 carbon atoms (also referred to as "number of carbon atoms"), and more preferably an alkyl group having 1 to 6 carbon atoms. The aryl group is preferably an aryl group having 6 to 18 carbon atoms, and more preferably an aryl group having 6 to 12 carbon atoms. The alkoxy group is preferably an alkoxy group having 1 to 12 carbon atoms, and more preferably an alkoxy group having 1 to 6 carbon atoms. The aryloxy group is preferably an aryloxy group having 6 to 18 carbon atoms, and more preferably an aryloxy group having 6 to 12 carbon atoms.
Among these, from the viewpoints of sensitivity and adhesion to a substrate, it is preferable that R ₁₅ to R ₁₉ are each independently one selected from a hydrogen atom, a halogen atom, a nitro group and an alkoxy group, and more preferably a hydrogen atom.

-Group having three or more condensed rings-
The group having three or more condensed rings may be aromatic or non-aromatic, but is preferably aromatic from the viewpoints of sensitivity and adhesion to a substrate.
The group having three or more condensed rings may or may not contain a heteroatom. From the viewpoints of sensitivity and adhesion to a substrate, the group having three or more condensed rings preferably contains a heteroatom.

From the viewpoint of sensitivity and adhesion to substrates, the number of rings contained in the group having three or more condensed rings is preferably 3 to 8, more preferably 3 to 6, even more preferably 3 or 6, and particularly preferably 3.

From the viewpoint of sensitivity and adhesion to substrates, the number of carbon atoms in the group having 3 or more condensed rings is preferably 12 to 50, more preferably 12 to 40, and even more preferably 12 to 30.

Examples of groups having three or more condensed rings include anthracene, pyrene, fluorenone, fluorene, acridine, dihydroacridine, acridone, carbazole, dibenzothiophene, dibenzofuran, xanthene, xanthone, thioxanthone, etc. Among these, from the viewpoints of sensitivity and substrate adhesion, carbazole, dibenzothiophene, or dibenzofuran is preferred, dibenzothiophene or dibenzofuran is more preferred, and dibenzofuran is even more preferred.

The group having three or more condensed rings may or may not have a substituent.
The substituent is not particularly limited, and is preferably a substituent having 0 to 100 carbon atoms, more preferably a substituent having 0 to 50 carbon atoms. Examples of the substituent include a halogen atom, a hydroxyl group, a thiol group, an amino group, an alkyl group, a cycloalkyl group, an alkenyl group, a heterocyclic group, an aryl group, an aryloxy group, a heteroaryl group, an acyl group, a nitro group, a cyano group, a sulfo group, an alkylaminocarbonyl group, an alkoxycarbonyl group, an alkylthio group, an arylthio group, a morpholino group, an alkoxyalkyl group, a carboxyl group, a carboxyalkyl group, and the like. These substituents may further have a substituent, or the substituents may be bonded to each other to form a ring structure.
Among these, the group having three or more condensed rings preferably has an acyl group as a substituent. Examples of the acyl group include an alkylcarbonyl group, an arylcarbonyl group, a heteroarylcarbonyl group, and the like, and an arylcarbonyl group or a heteroarylcarbonyl group is preferable. Examples of the aryl group in the arylcarbonyl group include a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a tolyl group, a xylyl group, a mesityl group, a 2-methoxyphenyl group, and a 2-bromophenyl group. Examples of the heteroaryl group in the heteroarylcarbonyl group include a 2-furyl group, a 3-furyl group, a 2-thienyl group, a 3-thienyl group, a 2-benzofuryl group, a 3-benzofuryl group, a 2-benzothienyl group, and a 3-benzothienyl group.

Preferred specific examples of groups with 3 or more condensed rings are shown below, but are not limited to these. Note that * indicates the bonding position to a carbon atom or nitrogen atom. Also, R represents a hydrogen atom or an alkyl group with 1 to 10 carbon atoms.

-(keto)oxime ester group-
The (keto)oxime ester group is not particularly limited as long as it has a (keto)oxime ester structure.
In one embodiment, the (keto)oxime ester group is preferably a group represented by the following formula (6). In formula (6), either of the two * marks represents a bonding position with a group having an indole skeleton. Specifically, when the (keto)oxime ester group is a ketoxime ester group, the * mark in the carbonyl group represents a bonding position with a group having an indole skeleton, and when the (keto)oxime ester group is an oxime ester group, the * mark in the oxime ester group represents a bonding position with a group having an indole skeleton.

In formula (6), Y ₁ represents a hydrogen atom, an alkyl group, or an aryl group;
R ₁ represents an alkyl group, an aryl group, a heteroaryl group, an alkoxy group, an aryloxy group, or a heteroaryloxy group;
n represents 0 or 1.

_--Y1--
In formula (6), _Y1 represents a hydrogen atom, an alkyl group or an aryl group.
The alkyl group is preferably an alkyl group having 1 to 30 carbon atoms, and more preferably an alkyl group having 1 to 20 carbon atoms.
The aryl group is preferably an aryl group having 6 to 30 carbon atoms, and more preferably an aryl group having 6 to 20 carbon atoms.
Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a decyl group, a dodecyl group, a stearyl group, an isopropyl group, an isoamyl group, a cyclopentyl group, a cyclohexyl group, a cyclopentylmethyl group, a cyclopentylethyl group, a cyclopentylpropyl group, and the like. These alkyl groups may be further substituted with a substituent consisting of a combination of O, S, N atoms, (C=O), and the like. These alkyl groups may be substituted with an aryl group or a heteroaryl group.
As the preferable optionally substituted alkyl group, it is also preferable that it has a substituent shown in <Group A>.
- Group A -
Cyano group, alkenyl group, alkynyl group, -NArAr', -SAr, -COOH, -OH, -O-COR _c , -O-CO-OR _c , -CONR _a Rb, -NR _a -CO-R _b , -O-CO-NR _a R _b , -NR _a -CO-OR _b , -NR _a -CO-NR _a R _b , -SO-R _c , -SO ₂ -R _c , -O-SO ₂ -R _c , -SO ₂ -NR _a R _b , -NR _a -SO ₂ -R _a , -CO-NR _a -COR _b , -CO-NR _a -SO ₂ -R _b , -SO ₂ -NR _a -CO-R _b , -SO ₂ -NR _a -SO ₂ -R _c , -Si(R _a ) _L (OR _b ) _m and heterocyclic groups,
Ar and Ar′ each independently represent an aryl group or a heteroaryl group;
R _a and R _b each independently represent a hydrogen atom, an alkyl group, an aryl group, or a heteroaryl group;
_Rc represents an alkyl group, an aryl group or a heteroaryl group; L and m each independently represent an integer of 0 to 3, and L+m=3 is satisfied.

Examples of the aryl group include a phenyl group, a tolyl group, a xylyl group, a funatyl group, an anthracenyl group, a pyrenyl group, etc. These alkyl groups may be further substituted with a substituent consisting of a combination of O, S, N atoms, (C=O), etc.
The group represented by Y ₁ may further have a substituent. Examples of the substituent include the substituents described above.

From the viewpoints of sensitivity and adhesion to a substrate, Y ₁ in formula (6) is preferably a group represented by the following formula (3).

In formula (3),
_R2 represents an alkyl group, provided that when _L2 is CHR, _R2 may be a hydrogen atom;
_R3 represents a hydrogen atom or an alkyl group;
_R4 represents an alkyl group;
_L1 and _L2 each independently represent CHR, O, S, or NR, and each R independently represents a hydrogen atom or an alkyl group;
Two or more of R ₂ , R ₃ , R ₄ and R may be bonded to each other to form a ring structure;
_Z2 represents a single bond or an alkylene group having 1 to 6 carbon atoms;
* indicates the linkage to the oxime group.

In terms of sensitivity and adhesion to a substrate, R ₂ in formula (3) is preferably an alkyl group having 1 to 10 carbon atoms.
In terms of sensitivity and adhesion to a substrate, R ₃ in formula (3) is preferably a hydrogen atom.
In terms of sensitivity and adhesion to a substrate, R ₄ in formula (3) is preferably an alkyl group having 1 to 10 carbon atoms.
In particular, from the viewpoints of sensitivity and adhesion to a substrate, it is preferable that _R2 and _R4 are bonded to each other to form a ring structure, and it is more preferable that _R2 and _R4 are bonded to each other to form an aliphatic hydrocarbon ring structure.
In terms of sensitivity and adhesion to a substrate, L ₁ in formula (3) is preferably O, S or NR, and more preferably O or NR.
In terms of sensitivity and adhesion to a substrate, _L2 in formula (3) is preferably CHR.
From the viewpoints of sensitivity and adhesion to a substrate, R in the above NR is preferably an alkyl group, more preferably an alkyl group having 1 to 10 carbon atoms, more preferably a methyl group or a cycloalkyl group, and particularly preferably a methyl group, a cyclopentyl group, or a cyclohexyl group.
In terms of sensitivity and adhesion to a substrate, R in the above CHR is preferably a hydrogen atom.
In terms of sensitivity and adhesion to a substrate, _Z2 in formula (3) is preferably a single bond or an alkylene group having 1 to 4 carbon atoms, more preferably a single bond, a methylene group or an ethylene group, and particularly preferably a single bond.

From the viewpoints of sensitivity and adhesion to a substrate, Y ₁ in formula (6) is preferably a group represented by the following formula (4).

In formula (4),
_L3 and _L4 each independently represent CHR, O, S, or NR, and at least one of _L3 and _L4 is CHR, in which R represents a hydrogen atom or an alkyl group;
Each _R5 independently represents a hydrogen atom or an alkyl group;
r represents an integer from 1 to 6;
* indicates the linkage to the oxime group.

In terms of sensitivity and adhesion to a substrate, _L3 in formula (4) is preferably O, S or NR.
In terms of sensitivity and adhesion to a substrate, _L4 in formula (4) is preferably CHR.
The preferred embodiments of R in formula (4) are the same as the preferred embodiments of R in formula (3).
In terms of sensitivity and adhesion to a substrate, R ₅ in formula (4) is preferably a hydrogen atom.
In the formula (4), r is preferably an integer of 3 to 5, more preferably 3 or 4, and particularly preferably 3, from the viewpoints of sensitivity and adhesion to a substrate.

Preferred specific examples of _Y1 in formula (6) are shown below, but are not limited thereto: In addition, * indicates the bonding position with the oxime group.

Among these, from the viewpoints of sensitivity and adhesion to a substrate, _Y1 is preferably at least one group selected from the group consisting of Y-26 to Y-29, and more preferably at least one group selected from the group consisting of Y-27 to Y-29.

^--R1--
In formula (6), R ₁ represents an alkyl group, an aryl group, a heteroaryl group, an alkoxy group, an aryloxy group, or a heteroaryloxy group.
From the viewpoints of sensitivity and adhesion to a substrate, R ₁ is preferably an alkyl group, more preferably an alkyl group having 1 to 6 carbon atoms, even more preferably an alkyl group having 1 to 4 carbon atoms, and particularly preferably a methyl group.
The aryl group is preferably an aryl group having 6 to 20 carbon atoms, and more preferably an aryl group having 6 to 12 carbon atoms.
The heteroaryl group is preferably a heteroaryl group having 4 to 20 carbon atoms, and more preferably a heteroaryl group having 4 to 10 carbon atoms.
The alkoxy group is preferably an alkoxy group having 1 to 6 carbon atoms, and more preferably an alkoxy group having 1 to 4 carbon atoms.
The aryloxy group is preferably an aryloxy group having 6 to 20 carbon atoms, and more preferably an aryloxy group having 6 to 12 carbon atoms.
The heteroaryloxy group is preferably a heteroaryloxy group having 4 to 20 carbon atoms, and more preferably a heteroaryloxy group having 4 to 10 carbon atoms.
The group represented by R ₁ may further have a substituent. Examples of the substituent include the substituents described above.

---n--
In the formula (6), n is preferably 0 from the viewpoints of sensitivity and adhesion to the substrate.

From the viewpoint of sensitivity and adhesion to the substrate, the specific radical polymerization initiator is preferably a compound represented by the following formula (1):

In formula (1),
_Z1 represents any one of an alkyl group, an aryl group, a heteroaryl group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, a hydroxyl group, a carboxyl group, a cyano group, a nitro group, a halogen atom, and an acyl group;
X represents a group having three or more condensed rings;
L represents a single bond or a divalent organic group;
R ₁₅ to R ₁₉ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a nitro group, an alkoxy group, or an aryloxy group, two or more of R ¹⁵ to R ¹⁹ may be bonded to each other to form a ring structure, and the ring structure thus formed may be an aromatic ring;
Y ₁ represents a hydrogen atom, an alkyl group or an aryl group;
R ₁ represents an alkyl group, an aryl group, a heteroaryl group, an alkoxy group, an aryloxy group, or a heteroaryloxy group;
m and n each independently represent 0 or 1.

_--Z1--
_Z1 in formula (1) represents any one of an aryl group, a heteroaryl group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, a hydroxyl group, a carboxyl group, a cyano group, a nitro group, a halogen atom, and an acyl group.
From the viewpoints of sensitivity and adhesion to a substrate, _Z1 is preferably at least one group selected from the group consisting of an aryl group, a heteroaryl group, and an arylthio group, more preferably at least one group selected from the group consisting of an aryl group and a heteroaryl group, still more preferably at least one group selected from the group consisting of an aryl group having 6 to 15 carbon atoms and a heteroaryl group having 6 to 15 carbon atoms, and particularly preferably at least one group selected from the group consisting of an aryl group having 6 to 12 carbon atoms and a heteroaryl group having 6 to 12 carbon atoms.
The group represented by Z ₁ may further have a substituent. Examples of the substituent include the substituents described above.
An embodiment of the substituent includes an alkylene group, O, S, NR, a carbonyl group, a sulfoxy group, a sulfonyl group, and the like, and the substituent may be bonded to X in formula (1) via any of these.

Preferred specific examples of _Z1 in formula (1) are shown below, but are not limited thereto: In addition, * indicates the bonding position to the carbon atom of X.

Among these, from the viewpoints of sensitivity and adhesion to a substrate, _Z1 is preferably at least one group selected from the group consisting of Z-1 to Z-10, Z-17 to Z-18, Z-25, and Z-31, and more preferably at least one group selected from the group consisting of Z-2, Z-5, Z-6, Z-17, Z-25, and Z-31.

---X--
X in formula (1) is a group having three or more condensed rings. The description of the group having three or more condensed rings is omitted here since it has been described above.
Preferred specific examples of X in formula (1) are shown below, but the invention is not limited thereto. In addition, * indicates the bonding position to a carbon atom or a nitrogen atom.

In particular, from the viewpoint of sensitivity and substrate adhesion, X is preferably at least one group selected from the group consisting of X-1 to X4, and more preferably at least one group selected from the group consisting of X-2 and X-3.

---L--
In formula (1), L represents a single bond or a divalent organic group, and from the viewpoints of sensitivity and adhesion to a substrate, it is preferably a divalent organic group.
Examples of the divalent organic group include an aromatic group and a heteroaromatic group.
From the viewpoints of sensitivity and adhesion to a substrate, the divalent organic group is preferably an arylene group.
The divalent organic group may further have a substituent, such as those mentioned above.
An embodiment of the substituent includes an alkylene group, O, S, NR, a carbonyl group, a sulfoxy group, a sulfonyl group, and the like, and the substituent may be bonded to X in formula (1) via any of these.
Preferred embodiments of R in NR are the same as those of R in formula (3).

Preferred specific examples of L in formula (1) are shown below, but are not limited to these. Note that * indicates the bonding position with the carbon atom of X or the nitrogen atom of the indole skeleton.

In particular, from the viewpoint of sensitivity and adhesion to the substrate, L is preferably at least one group selected from the group consisting of L-10, L-11, and L-13, and L-13 is more preferable.

_--R15 to _R19 --
Preferred embodiments of R ₁₅ to R ₁₉ in formula (1) are the same as those in formula (5), and therefore description thereof will be omitted here.

_--Y1--
In formula (1), _Y1 represents a hydrogen atom, an alkyl group or an aryl group.
Preferred embodiments of _Y1 are the same as those of formula (6), and therefore will not be described here.

^--R1--
In formula (1), R ₁ represents an alkyl group, an aryl group, a heteroaryl group, an alkoxy group, an aryloxy group, or a heteroaryloxy group.
Preferred embodiments of _R1 are the same as those of formula (6), and therefore will not be described here.

--m and n--
In the formula (1), m is preferably 1 from the viewpoints of sensitivity and adhesion to a substrate.
In the formula (1), n is preferably 0 from the viewpoints of sensitivity and adhesion to a substrate.

Preferred specific examples of the specific radical polymerization initiator represented by the above formula (1) include A-1 to A-199 shown in Tables 1 to 5, but needless to say, are not limited to these.
In addition, Z-1 to Z-31, X-1 to X-21, L-1 to L21, and Y-1 to Y-25 are the same groups as Z-1 to Z-31, X-1 to X-21, L-1 to L21, and Y-1 to Y-25 described above, respectively. In addition, in Table 1, Ph represents a phenyl group, and tBu represents a tert-butyl group.

From the viewpoint of sensitivity and adhesion to the substrate, the specific radical polymerization initiator is preferably a compound represented by the following formula (2).

In formula (2),
Ar ₁ represents an alkyl group, an aryl group, or a heteroaryl group;
_Ar2 represents a divalent organic group;
_X11 and _X12 each independently represent a single bond, O, S, _NR , _CRxRy , or C=O; R, _Rx , and _Ry each independently represent a hydrogen atom, an alkyl group, or an aryl group;
R ₁₁ and R ₁₂ each independently represent an alkyl group, an aryl group, a halogen atom, a nitro group, a hydroxyl group, an alkoxy group, an aryloxy group, an alkylthio group, or an arylthio group;
R ₁₅ to R ₁₉ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a nitro group, an alkoxy group, or an aryloxy group, two or more of R ¹⁵ to R ¹⁹ may be bonded to each other to form a ring structure, and the ring structure thus formed may be an aromatic ring;
Y ₁ represents a hydrogen atom, an alkyl group or an aryl group;
R ₁ represents an alkyl group, an aryl group, a heteroaryl group, an alkoxy group, an aryloxy group, or a heteroaryloxy group;
m and n each independently represent 0 or 1;
p and q each independently represent an integer of 0 to 3.
Preferred embodiments of R ₁₅ to R ₁₉ , Y ₁ , R ₁ , m and n are the same as those of formula (1), and therefore description thereof will be omitted here.

--Ar ₁ --
Ar ₁ in formula (2) represents any one of an aryl group, a heteroaryl group, a naphthylene group, a heteronaphthylene group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, a hydroxyl group, a carboxyl group, a cyano group, a nitro group, a halogen atom, and an acyl group.
From the viewpoints of sensitivity and adhesion to a substrate, Ar ₁ is preferably at least one group selected from the group consisting of an aryl group, a heteroaryl group, a naphthylene group, a heteronaphthylene group, and an arylthio group, more preferably at least one group selected from the group consisting of an aryl group and a heteroaryl group, still more preferably at least one group selected from the group consisting of an aryl group having 6 to 15 carbon atoms and a heteroaryl group having 6 to 15 carbon atoms, and particularly preferably at least one group selected from the group consisting of an aryl group having 6 to 12 carbon atoms and a heteroaryl group having 6 to 12 carbon atoms.
The group represented by Ar ₁ may further have a substituent. Examples of the substituent include the substituents described above.

Preferred specific examples of Ar ₁ in formula (2) are shown below, but are not limited thereto: In addition, * indicates the bonding position to the carbon atom of the carbonyl group.

Among these, from the viewpoints of sensitivity and adhesion to a substrate, Ar ₁ is preferably at least one group selected from the group consisting of Ar-1 to Ar-10, Ar-17 to Ar-18, Ar-25, and Ar-31, and more preferably at least one group selected from the group consisting of Ar-2, Ar-5, Ar-6, Ar-17, Ar-25, and Ar-31.

_--Ar2--
_Ar2 in formula (2) is a divalent organic group. Preferred embodiments of the divalent organic group are the same as those of L in formula (1), and therefore will not be described here.

_--X11 and _X12 --
In formula (2), _X11 and _X12 each independently represent a single bond, O, S, NR, _CRxRy _, or C=O, and R, _Rx , and _Ry each independently represent a hydrogen atom, an alkyl group, or an aryl group.
From the viewpoints of sensitivity and adhesion to a substrate, it is preferable that one of X ₁₁ and X ₁₂ is a single bond and the other is O, S, NR or CR _x R _y , and it is more preferable that the other is O or S.
R _x and R _y in CR _x R _y are preferably a hydrogen atom, an alkyl group, or an aryl group, more preferably an alkyl group or an aryl group, and further preferably an alkyl group.
Preferred embodiments of R in NR are the same as those of R in formula (3).

--p and q--
In formula (2), p and q each independently represent an integer of 0 to 3, and from the viewpoints of sensitivity and adhesion to a substrate, are preferably 0 or 1, and more preferably 0.

Specific examples of the specific radical polymerization initiator represented by the above formula (2) include A-29 to A-167 and A-172 to A-195 shown in Tables 1 to 4, but needless to say, are not limited to these.

The specific radical polymerization initiator preferably absorbs light having a wavelength of 190 nm to 450 nm, more preferably has absorption in any one of the ArF absorption region of 193 nm, the KrF absorption region of 248 nm, and the i-line absorption region of 365 nm, and further preferably has absorption in any one of the ArF absorption region of 193 nm and the KrF absorption region of 248 nm.
The gram absorption coefficient of the specific radical polymerization initiator at a wavelength of 248 nm or 365 nm is preferably 10,000 L g ^-1 cm ^-1 or more, more preferably 30,000 L g ^-1 cm ^-1 or more, even more preferably 50,000 L g ^-1 cm ^-1 or more, and particularly preferably 70,000 L g ^-1 cm ^-1 or more, from the viewpoint of sensitivity and substrate adhesion. The upper limit of the gram absorption coefficient is not particularly limited, and can be 200,000 L g ^-1 cm ^-1 or less.
The method for measuring the gram absorption coefficient of the specific radical polymerization initiator is as follows.
Weigh out 12.5 mg of the specific radical polymerization initiator and place it in a 100 mL volumetric flask. Add acetonitrile to this and dissolve it completely. Take 2 mL of this initiator solution with a whole pipette and fill it up in a 25 mL volumetric flask, and use this as the measurement sample.
A measurement sample was placed in a quartz glass cell (volume 5 mL) of 1 cm square, and UV (ultraviolet) measurement was carried out in air.
As the UV measuring device, an ultraviolet-visible-near infrared spectrophotometer UH4150 manufactured by Hitachi High-Tech Science Corp. or a device equivalent thereto can be used.

In light having a wavelength of 200 nm to 450 nm, the maximum absorption wavelength of the specific radical polymerization initiator is preferably between 200 nm and 300 nm, more preferably between 220 nm and 280 nm, and even more preferably between 240 nm and 260 nm, from the viewpoints of sensitivity and adhesion to a substrate.
The method for measuring the maximum absorption wavelength of the specific radical polymerization initiator is as follows.
An absorption spectrum is obtained in 1 nm increments in the range of 190 nm to 800 nm using the same method as for measuring the gram absorption coefficient of the specific radical polymerization initiator. The value of the absorption wavelength with the highest absorbance is read.

From the viewpoint of sensitivity and adhesion to a substrate, the absorption edge on the long wavelength side of the specific radical polymerization initiator is preferably 400 nm or less, more preferably 380 nm or less. The lower limit of the absorption edge is not particularly limited, and can be 100 nm or more.
The method for measuring the absorption edge on the long wavelength side of the specific radical polymerization initiator is as follows.
An absorption spectrum is obtained in 1 nm increments in the 190 nm to 800 nm region by the same method as for measuring the gram absorption coefficient of the specific radical polymerization initiator. The shortest wavelength at which the gram absorption coefficient is 100 or less at the long wave end is read.

From the viewpoint of sensitivity and adhesion to the substrate, the molecular weight of the specific radical polymerization initiator is preferably less than 1500, more preferably less than 1200, even more preferably less than 1000, and particularly preferably less than 800. There is no particular lower limit to the molecular weight of the specific radical polymerization initiator, but it is preferably 200 or more, more preferably 300 or more, and even more preferably 400 or more.

From the viewpoints of sensitivity and adhesion to a substrate, the melting point of the specific radical polymerization initiator is preferably less than 300° C., more preferably less than 250° C., even more preferably less than 200° C., and particularly preferably less than 150° C. The lower limit of the melting point is not particularly limited, and from the viewpoint of handling, it is preferably 30° C. or higher, and more preferably 70° C. or higher.
In this disclosure, "melting point" is a value measured using a melting point measuring apparatus.
As a melting point measuring device, for example, "MP80" (manufactured by Mettler Toledo) is used.
The melting point is measured by heating 5 mg of a sample from 20° C. to 300° C. at a constant temperature increase rate (5° C./min), and reading the temperature at the minimum value of the melting point peak.

From the viewpoints of sensitivity and adhesion to a substrate, the solubility of the specific radical polymerization initiator in propylene glycol monomethyl ether acetate is preferably 1 mass % or more, more preferably 5 mass % or more, and particularly preferably 10 mass % or more.
The solubility of the specific radical polymerization initiator in propylene glycol monomethyl ether acetate means the amount of the specific radical polymerization initiator dissolved in propylene glycol monomethyl ether acetate at 25°C.

From the viewpoints of sensitivity and adhesion to a substrate, the HPLC purity of the specific radical polymerization initiator is preferably 98% or more, and more preferably 99% or more.
The HPLC purity of the specific radical polymerization initiator is measured using a high performance liquid chromatography device under the following conditions. As the high performance liquid chromatography device, for example, a device manufactured by Agilent can be used.
(Measurement condition)
Column oven temperature: 40°C
Elution solvent: tetrahydrofuran/water=70/30 (by mass). The elution solvent contained 1% by mass each of acetic acid and triethylamine as buffers.

From the viewpoints of sensitivity and adhesion to a substrate, the proportion of carboxyl groups contained in the specific radical polymerization initiator is preferably 1 mass % or less, more preferably 0.1 mass % or less, and even more preferably 0.01 mass % or less, and particularly preferably less than 1 ppm by mass, relative to the total mass of the specific radical polymerization initiator.
The proportion of carboxyl groups contained in the specific radical polymerization initiator is measured by gas chromatography.

The curable composition according to the present disclosure may contain one specific radical polymerization initiator alone or two or more specific radical polymerization initiators. When two or more specific radical polymerization initiators are used, the total amount of the specific radical polymerization initiators is preferably within the following range.
From the viewpoints of sensitivity and substrate adhesion, the content of the specific radical polymerization initiator is preferably 0.01% by mass to 30% by mass, more preferably 0.05% by mass to 25% by mass, even more preferably 0.1% by mass to 20% by mass, and particularly preferably 1% by mass to 15% by mass, based on the total solid content of the curable composition. Furthermore, by setting the content of the specific radical polymerization initiator to 30% by mass or less, it is possible to suppress the generation of residues in the cured product of the curable composition of the present disclosure.

Moreover, the specific radical polymerization initiator preferably has no absorption at wavelengths of 450 nm or more, more preferably has no absorption at wavelengths of 420 nm or more, and particularly preferably has no absorption in the wavelength range longer than 400 nm. In the present disclosure, "having no absorption" means that the gram absorption coefficient at that wavelength is 100 L·g ^-1 ·cm ^-1 or less. The specific radical polymerization initiator is preferably white to light yellow. The above colors are preferable because they have little effect on the spectrum of the color filter.

The method for producing the specific radical polymerization initiator is not particularly limited, and the specific radical polymerization initiator may be produced by a known method or may be produced with reference to a known method.
The above-mentioned production method includes, for example, the following method.
A compound having a group in which three or more rings are condensed is reacted with a Lewis acid (e.g., aluminum chloride) via the Friedel-Crafts reaction to carry out acylation, and further acylation with an acid chloride having a halogen atom such as a fluorine atom.
After acylation, the intermediate (I) is obtained by a nucleophilic aromatic reaction with an indole compound having a carbonyl group.
Hydroxylamine is added to the carbonyl group of intermediate (I) to form an oxime, which is then finally protected as an ester to give an oxime ester compound.

(Regarding reactions)
The oxime-forming reaction by addition of hydroxylamine to a ketone can be suitably carried out preferably in the temperature range of -20°C to 120°C, more preferably -10°C to 80°C, and even more preferably 0°C to 50°C. The solvent that can be used is not particularly limited, but is preferably a solvent that is miscible with hydroxylamine hydrochloride. Examples of the solvent include water, methanol, ethanol, isopropanol, acetonitrile, tetrahydrofuran, pyridine, 4-(N-N-dimethyl)aminopyridine, aniline, 4-methylaniline, ethylene glycol, and propylene glycol. It is also preferable to use a base to neutralize hydroxylamine hydrochloride. Examples of the base include, but are not limited to, sodium acetate, lithium acetate, cesium acetate, sodium hydroxide, sodium methoxide, potassium t-butoxide, triethylamine, pyridine, and aniline.

(Dioxime/trioxime by-products)
In the intermediate (I), when a plurality of carbonyl groups are present in one molecule, the carbonyl group to be oximed may not be only one. For example, a dioxime in which two carbonyl groups are oximed, or a trioxime in which three carbonyl groups are oximed may be present. These dioximes and trioximes are turned into dioxime esters or trioxime esters through an esterification step. The esterification may be such that not only two hydroxyl groups of a dioxime are esterified, but also one of the hydroxyl groups of a dioxime is esterified, not only three hydroxyl groups of a trioxime are esterified, but also one of the hydroxyl groups of a trioxime is esterified, or any two hydroxyl groups of a trioxime are esterified.
When a dioxime, a dioxime ester, a trioxime, or a trioxime ester is contained, the total amount is preferably 0.001% by mass to 10% by mass, more preferably 0.001% by mass to 8% by mass, and even more preferably 0.001% by mass to 5% by mass, relative to the specific radical polymerization initiator of the present disclosure. By keeping the total amount within this range, higher sensitivity can be maintained.
Examples of dioximes and trioximes are given below.

(Precursor and intermediate impurities)
The specific radical polymerization initiator (monoxime ester initiator) of the present disclosure may contain an oxime body as a precursor, and a ketone body (intermediate (I)) prior to oximation. The content of each of the oxime body and the ketone body (intermediate (I)) in the specific radical polymerization initiator of the present disclosure is preferably 0.001% by mass to 10% by mass, more preferably 0.001% by mass to 8% by mass, even more preferably 0.001% by mass to 5% by mass, and most preferably 0.001% by mass to 1% by mass. By keeping the content within this range, higher sensitivity can be maintained.

(For mixed oxime E/Z isomers)
The specific radical polymerization initiator of the present disclosure is an oxime compound, and may have stereoisomers of E and Z. The oxime compound may be either E or Z unless otherwise specified. The oxime compound may also be in a mixed form of E and Z. When the oxime compound is in a mixed form of E and Z, the mass ratio [E:Z] of E and Z isomers is preferably 99.9:0.1 to 80:20 or 20:80 to 0.1:99.9, and more preferably 99.9:0.1 to 90:10 or 10:90 to 0.1:99.9. By keeping the ratio within this range, higher sensitivity can be maintained.

Another production method is to oxime the α-position of the carbonyl group of intermediate (I) using isoamyl nitrite under acid or base conditions, and then finally protect the ester. This makes it possible to produce a specific radical polymerization initiator having a ketoxime ester group.

The curable composition according to the present disclosure may include an organic acid.
An example of the organic acid is R ₁ COOH. R ₁ is as described above.
R ₁ COOH may be one that is generated and remains during the synthesis of the specific radical polymerization initiator, or may be one that is generated by hydrolysis of the specific radical polymerization initiator.
The upper limit of the organic acid content relative to the total mass of the curable composition according to the present disclosure is preferably 1000 mass ppm or less, more preferably 500 mass ppm or less, and even more preferably 100 mass ppm or less. The lower limit of the organic acid content is not particularly limited, and may be 0.1 mass ppm or more, or 1 mass ppm or more.

The specific radical polymerization initiator may contain impurities such as organic acids, metals, moisture, organic solvents, and halogen ions.
The organic acid is as described above. The upper limit of the content of the organic acid relative to the total mass of the specific radical polymerization initiator is preferably 5000 mass ppm or less, more preferably 1000 mass ppm or less, more preferably 500 mass ppm or less, and even more preferably 100 mass ppm or less. The lower limit of the content of the organic acid is not particularly limited, and may be 0.1 mass ppm or more, or 1 mass ppm or more.

Examples of metals include Al, Ca, Cu, Cr, Mg, Fe, Mn, Ni, Co, Cd, Li, Pb, Na, K, Zn, P, Ag, Ti, Sn, and Si.
The upper limit of the metal content relative to the total mass of the specific radical polymerization initiator is preferably 1000 mass ppm or less, more preferably 500 mass ppm or less, and even more preferably 100 mass ppm or less. The lower limit of the metal content is not particularly limited, and may be 0.1 mass ppm or more, or 1 mass ppm or more.
The above content is the content of one type of metal, and when the specific radical polymerization initiator contains two or more types of metals, the above content may be used for each of them.

The upper limit of the moisture content relative to the total mass of the specific radical polymerization initiator is preferably 5000 mass ppm or less, more preferably 1000 mass ppm or less, more preferably 500 mass ppm or less, and even more preferably 100 mass ppm or less. The lower limit of the moisture content is not particularly limited, and may be 0.1 mass ppm or more, or 1 mass ppm or more.

The organic solvent is not particularly limited, and examples thereof include methanol, ethanol, propanol, 2-propanol, butanol, methyl acetate, ethyl acetate, hexane, heptane, acetonitrile, N-N-dimethylformamide, N-N-dimethylacetamide, N-methylpyrrolidone, N-ethylpyrrolidone, 1,3-dimethyl-2-imidazolidinone, dimethyl sulfoxide, acetone, methyl ethyl ketone, diethyl ether, diisopropyl ether, t-butyl methyl ether, dibutyl ether, tetrahydrofuran, toluene, chlorobenzene, o-dichlorobenzene, triethylamine, pyridine, diisopropylamine, acetic acid, etc. Solvents described below may also be used.
The upper limit of the content of the organic solvent relative to the total mass of the specific radical polymerization initiator is preferably 5000 mass ppm or less, more preferably 1000 mass ppm or less, more preferably 500 mass ppm or less, and even more preferably 100 mass ppm or less. The lower limit of the content of the organic solvent is not particularly limited, and may be 0.1 mass ppm or more, or 1 mass ppm or more.

Halogen ions include F ⁻ , Cl ⁻ , Br ⁻ , and I ⁻ .
The upper limit of the halogen ion content relative to the total mass of the specific radical polymerization initiator is preferably 5000 mass ppm or less, more preferably 1000 mass ppm or less, more preferably 500 mass ppm or less, and even more preferably 100 mass ppm or less. The lower limit of the halogen ion content is not particularly limited, and may be 0.1 mass ppm or more, or 1 mass ppm or more. The counter cation of the halogen ion is not particularly limited.

<Other radical polymerization initiators>
The curable composition according to the present disclosure may contain a radical polymerization initiator other than the specific radical polymerization initiator.
Other radical polymerization initiators include oxime compounds, α-aminoacetophenone compounds, α-hydroxyketone compounds, acylphosphine compounds, and the like.
Of these, oxime compounds are preferred.
By using the radical polymerization initiator represented by the above formula (1) in combination with another radical polymerization initiator, a more well-balanced pattern with good rectangularity can be obtained.

Examples of the oxime compound include the compounds described in paragraphs 0142 to 0149 of WO 2022/085485, the polymers described in JP 2020-172619 A, the compounds represented by formula (1) described in WO 2020/152120, and the oxime ester compounds described in WO 2021/023144.
A specific example of the oxime compound is TR-PBG-327 (manufactured by Tronley Corporation).
Other radical polymerization initiators include fluorenyl amino ketone photoinitiators described in JP-T-2020-507664, photopolymerization initiators represented by the general formula (1) of JP-A-2021-173858, photopolymerization initiators described in paragraphs 0022 to 0024 of JP-A-2021-173858, photopolymerization initiators represented by the general formula (1) of JP-A-2021-170089, photopolymerization initiators described in paragraphs 0117 to 0120 of JP-A-2021-170089, compounds described in JP-A-2021-181406, and photopolymerization initiators described in JP-A-2022-013379. Initiator, compound represented by formula (1) described in JP-A-2022-015747, fluorine-containing fluorene oxime ester photoinitiator described in JP-T-2021-507058, initiator described in China Patent Application Publication No. 110764367, initiator described in JP-T-2022-518535, initiator described in WO 2021/175855, compound described in Taiwan Patent Application Publication No. 202200534, compound described in JP-A-2022-078550, compound described in Korean Patent Publication No. 10-2017-0087330, and the like can also be used.
In addition, as the oxime compound, the compounds described in paragraphs 0143 to 0149 of WO 2022/085485 can be used.
As the oxime compound, an oxime compound having an aromatic ring group Ar ^OX1 in which an electron-withdrawing group is introduced into the aromatic ring (hereinafter, also referred to as an oxime compound OX) can be used. Specific examples of the oxime compound OX include the compounds described in paragraphs 0083 to 0105 of Japanese Patent No. 4600600.

Examples of the oxime compounds include compounds described in JP-A-2001-233842, compounds described in JP-A-2000-080068, compounds described in JP-A-2006-342166, compounds described in J. C. S. Perkin II (1979, pp. 1653-1660), compounds described in J. C. S. Perkin II (1979, pp. 156-162), compounds described in Journal of Photopolymer Science and Technology (1995, pp. 202-232), compounds described in JP-A-2000-066385, compounds described in JP-T-2004-534797, compounds described in JP-A-2006-342166, compounds described in JP-A-2017-019766, compounds described in Japanese Patent No. 6065596, compounds described in WO 2015/152153, compounds described in WO 2017/051680, The compounds described in JP-A-2017-198865, the compounds described in paragraphs 0025 to 0038 of WO 2017/164127, the compounds described in WO 2013/167515, the polymers described in JP-A-2020-172619, the compounds represented by formula 1 described in WO 2020/152120, and the oxime ester compounds described in WO 2021/023144 can also be used.
Specific examples of the oxime compound include 3-benzoyloxyiminobutan-2-one, 3-acetoxyiminobutan-2-one, 3-propionyloxyiminobutan-2-one, 2-acetoxyiminopentan-3-one, 2-acetoxyimino-1-phenylpropan-1-one, 2-benzoyloxyimino-1-phenylpropan-1-one, 3-(4-toluenesulfonyloxy)iminobutan-2-one, 2-ethoxycarbonyloxyimino-1-phenylpropan-1-one, 1-[4-(phenylthio)phenyl]-3-cyclohexyl-propane-1,2-dione-2-(O-acetyloxime), and the like. Commercially available products include Irgacure OXE01, Irgacure OXE02, Irgacure OXE03, Irgacure OXE04 (all manufactured by BASF), TR-PBG-304, TR-PBG-327 (manufactured by Tronley), and ADEKA OPTOMER N-1919 (manufactured by ADEKA CORPORATION, photopolymerization initiator 2 described in JP-A-2012-014052).
In addition, it is also preferable to use, as the oxime compound, a compound that is not colored or a compound that is highly transparent and does not easily discolor. Commercially available products include ADEKA ARCLES NCI-730, NCI-831, and NCI-930 (all manufactured by ADEKA CORPORATION).
As another radical polymerization initiator, a fluorenyl amino ketone photoinitiator described in JP-A-2020-507664 can also be used.

As the oxime compound, an oxime compound having a fluorene ring can also be used. Specific examples of oxime compounds having a fluorene ring include the compounds described in JP 2014-137466 A, the compounds described in Japanese Patent No. 6636081 A, and the compounds described in Korean Patent Publication No. 10-2016-0109444.

As the oxime compound, an oxime compound having a skeleton in which at least one benzene ring of a carbazole ring is replaced with a naphthalene ring can also be used. Specific examples of such oxime compounds include the compounds described in WO 2013/083505.

As the oxime compound, an oxime compound having a fluorine atom can also be used. Specific examples of oxime compounds having a fluorine atom include the compounds described in JP-A-2010-262028, compounds 24, 36 to 40 described in JP-A-2014-500852, and compound (C-3) described in JP-A-2013-164471.

As the oxime compound, an oxime compound having a nitro group can be used. It is also preferable that the oxime compound having a nitro group is a dimer. Specific examples of oxime compounds having a nitro group include the compounds described in paragraphs 0031 to 0047 of JP 2013-114249 A, paragraphs 0008 to 0012 and 0070 to 0079 of JP 2014-137466 A, the compounds described in paragraphs 0007 to 0025 of Japanese Patent No. 4223071 A, and ADEKA ARCLES NCI-831 (manufactured by ADEKA Corporation).

As the oxime compound, an oxime compound having a benzofuran skeleton can also be used. Specific examples include OE-01 to OE-75 described in WO 2015/036910.

As the oxime compound, an oxime compound in which a substituent having a hydroxyl group is bonded to a carbazole skeleton can also be used. Examples of such photopolymerization initiators include the compounds described in WO 2019/088055.

As the oxime compound, an oxime compound having an aromatic ring group Ar ^OX1 in which an electron-withdrawing group is introduced into an aromatic ring (hereinafter, also referred to as oxime compound OX) can also be used. Examples of the electron-withdrawing group of the aromatic ring group Ar ^OX1 include an acyl group, a nitro group, a trifluoromethyl group, an alkylsulfinyl group, an arylsulfinyl group, an alkylsulfonyl group, an arylsulfonyl group, and a cyano group. An acyl group and a nitro group are preferred, and an acyl group is more preferred because it is easy to form a film with excellent light resistance, and a benzoyl group is even more preferred. The benzoyl group may have a substituent. The substituent is preferably a halogen atom, a cyano group, a nitro group, a hydroxy group, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, a heterocyclic group, a heterocyclic oxy group, an alkenyl group, an alkylsulfanyl group, an arylsulfanyl group, an acyl group, or an amino group, more preferably an alkyl group, an alkoxy group, an aryl group, an aryloxy group, a heterocyclic oxy group, an alkylsulfanyl group, an arylsulfanyl group, or an amino group, and further preferably an alkoxy group, an alkylsulfanyl group, or an amino group.

The curable composition according to the present disclosure also preferably contains an oxime ester compound represented by the following general formula:

In the above general formula, R ₁ and R ₂ each independently represent R ₁₁₁ , OR ₁₁₁ , COR ₁₁₁ , SR ₁₁₁ , CONR ₁₁₂ R ₁₁₃ or CN.
R ₁₁₁ , R ₁₁₂ and R ₁₁₃ each independently represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms, an arylalkyl group having 7 to 30 carbon atoms or a heterocyclic group having 2 to 20 carbon atoms; the hydrogen atoms of the groups represented by R ₁₁₁ , R ₁₁₂ and R ₁₁₃ can further be R ₁₂₁ , OR ₁₂₁ , COR ₁₂₁ , SR ₁₂₁ , NR ₁₂₂ R ₁₂₃ , CONR ₁₂₂ R ₁₂₃ , -NR ₁₂₂ -OR ₁₂₃ , -NCOR ₁₂₂ -OCOR ₁₂₃ , NR ₁₂₂ COR ₁₂₁ , OCOR ₁₂₁ , COOR ₁₂₁ , SCOR ₁₂₁ , OCSR ₁₂₁ , COSR ₁₂₁ , CSOR ₁₂₁ , a hydroxyl group, a nitro group, CN, a halogen atom, or COOR ₁₂₁ .
R ₁₂₁ , R ₁₂₂ and R ₁₂₃ each independently represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms, an arylalkyl group having 7 to 30 carbon atoms, or a heterocyclic group having 2 to 20 carbon atoms. The hydrogen atom of the group represented by R ₁₂₁ , R ₁₂₂ and R ₁₂₃ may be further substituted with a nitro group, CN, a halogen atom, a hydroxyl group or a carboxyl group.
The alkylene portions of the groups represented by R ₁₁₁ , R ₁₁₂ , R ₁₁₃ , R ₁₂₁ , R ₁₂₂ and R ₁₂₃ may be interrupted 1 to _{5 times} by -O-, -S-, -COO-, -OCO-, -NR -, -NR CO-, -NR _COO- , _-OCONR -, -SCO- _, -COS-, -OCS- or -CSO-, provided that the oxygen atoms are not adjacent. R _represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms, an arylalkyl group having 7 to 30 carbon atoms or a heterocyclic group having 2 to 20 carbon atoms. The alkyl moieties of the groups represented by R ₁₁₁ , R ₁₁₂ , R ₁₁₃ , R ₁₂₁ , R ₁₂₂ , R ₁₂₃ and R ₁₂₄ may have a branched side chain or may be a cyclic alkyl.

In the above general formula, _R3 represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms, an arylalkyl group having 7 to 30 carbon atoms, or a heterocyclic group having 2 to 20 carbon atoms. The alkyl portion of the group represented by _R3 may have a branched side chain or may be a cyclic alkyl.
Furthermore, _R3 and _R7 , _R3 and _R8 , _R4 and _R5 , _R5 and _R6 , and _R6 and _R7 may each be joined together to form a ring.
The hydrogen atoms in the group represented by _R3 may be further substituted by _R121 , _OR121 , _COR121 , _SR121 , _NR122R123 , CONR122R123 _, _-NR122 - _OR123 _, _-NCOR122 - _OCOR123 , _NR122COR121 , _OCOR121 , _COOR121 , _SCOR121 , _OCSR121 , _COSR121 , _CSOR121 , a hydroxyl _group , a nitro group, CN, _a halogen atom, or _COOR121 .

In the above general formula, R ₄ , R ₅ , R ₆ and R ₇ each independently represent R ₁₁₁ , OR ₁₁₁ , SR ₁₁₁ , COR ₁₁₄ , CONR ₁₁₅ R ₁₁₆ , NR ₁₁₂ COR ₁₁₁ , OCOR ₁₁₁ , COOR ₁₁₄ , SCOR ₁₁₁ , OCSR ₁₁₁ , COSR ₁₁₄ , CSOR ₁₁₁ , a hydroxyl group, CN or a halogen atom, and R ₄ and R ₅ , R ₅ and R ₆ , and R ₆ and R ₇ may each be joined together to form a ring. R ₁₁₄ , R ₁₁₅ and R ₁₁₆ each represent a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, and the alkyl portion of the group represented by R ₁₁₄ , R ₁₁₅ and R ₁₁₆ may have a branched side chain or may be a cyclic alkyl.

In the above general formula, _R8 represents _R111 _, _OR111 , SR111, _COR111 , _CONR112R113 , _NR112COR111 , _OCOR111 , _COOR111 , _SCOR111 _, _OCSR111 , _COSR111 , _CSOR111 , a hydroxyl group, _CN or a halogen atom.
In the above general formula, n represents 0 or 1.

Specific examples of oxime compounds OX include the compounds described in paragraphs 0083 to 0105 of Japanese Patent No. 4600600.

Furthermore, the following compounds are particularly preferred examples of oxime compounds:

The mass ratio when used in combination with other radical polymerization initiators is not particularly limited, but from the viewpoint of outgassing suppression, the content of the radical polymerization initiator represented by the above formula 1 is preferably 10 mass% or more, more preferably 50 mass% or more, even more preferably 80 mass% or more, and particularly preferably 90 mass% or more, based on the total mass of the polymerization initiator.

<Radically curable compound>
The curable composition according to the present disclosure comprises a radically curable compound.
The radically curable compound may, for example, be a compound having an ethylenically unsaturated group.

Examples of resin-type radically curable compounds include resins containing repeating units with radically polymerizable groups. The weight-average molecular weight (Mw) of the resin-type polymerizable compound is preferably 2,000 to 2,000,000. The upper limit of the weight-average molecular weight is more preferably 1,000,000 or less, and even more preferably 500,000 or less. The lower limit of the weight-average molecular weight is more preferably 3,000 or more, and even more preferably 5,000 or more.

The molecular weight of the monomer-type radically curable compound (polymerizable monomer) is preferably less than 2,000, and more preferably 1,500 or less. The lower limit of the molecular weight of the polymerizable monomer is preferably 100 or more, and more preferably 200 or more.

The compound having an ethylenically unsaturated group as a polymerizable monomer is preferably a 3-15 functional (meth)acrylate compound, and more preferably a 3-6 functional (meth)acrylate compound. Specific examples include the compounds described in paragraph 0128 of WO 2022/085485 and the compounds described in JP 2017-194662 A, the contents of which are incorporated herein by reference.

As a compound having an ethylenically unsaturated group, the compounds described in paragraphs 0129 to 0137 of WO 2022/085485 can also be used. The compound having an ethylenically unsaturated group may be a compound having an acid group such as a carboxyl group, a sulfo group, or a phosphate group, a compound having a caprolactone structure, a compound having an alkyleneoxy group, or a compound having a fluorene skeleton.

As compounds having an ethylenically unsaturated group, it is also preferable to use UA-7200 (manufactured by Shin-Nakamura Chemical Co., Ltd.), DPHA-40H (manufactured by Nippon Kayaku Co., Ltd.), UA-306H, UA-306T, UA-306I, AH-600, T-600, AI-600, LINC-202UA (manufactured by Kyoeisha Chemical Co., Ltd.), 8UH-1006, 8UH-1012 (all manufactured by Taisei Fine Chemical Co., Ltd.), Light Acrylate POB-A0 (manufactured by Kyoeisha Chemical Co., Ltd.), etc.

The content of the radical curable compound is preferably 0.1% by mass to 50% by mass based on the total solid content of the curable composition. The lower limit is more preferably 0.5% by mass or more, and even more preferably 1% by mass or more. The upper limit is more preferably 45% by mass or less, and even more preferably 40% by mass or less.
In the curable composition according to the present disclosure, the radical curable compound may be used alone or in combination with two or more kinds. When two or more kinds are used, it is preferable that the total amount of the radical curable compounds is in the above range.

<Coloring Agent>
The curable composition according to the present disclosure may contain a colorant.
Examples of the colorant include a chromatic colorant and a black colorant. Examples of the chromatic colorant include a colorant having a maximum absorption wavelength in the wavelength range of 400 nm to 700 nm. Examples of the chromatic colorant include a green colorant, a red colorant, a yellow colorant, a purple colorant, a blue colorant, and an orange colorant.
The colorant may be a pigment or a dye.
From the viewpoints of coloring property and dispersibility, the colorant is preferably at least one pigment selected from the group consisting of a diketopyrrolopyrrole pigment, a quinacridone pigment, an anthraquinone pigment, a perylene pigment, a phthalocyanine pigment, an isoindoline pigment, a quinophthalone pigment, an azo pigment, an azomethine pigment, and a dioxazine pigment, and more preferably at least one pigment selected from the group consisting of a diketopyrrolopyrrole pigment, a phthalocyanine pigment, and an isoindoline pigment.
As the colorant, a black pigment can be used, which may include one or more pigments selected from carbon black, titanium atoms, and zirconium atoms.

The average primary particle diameter of the pigment is preferably 1 nm to 200 nm. The lower limit is more preferably 5 nm or more, and even more preferably 10 nm or more. The upper limit is more preferably 180 nm or less, even more preferably 150 nm or less, and particularly preferably 100 nm or less. In this specification, the primary particle diameter of the pigment can be determined from an image photograph obtained by observing the primary particles of the pigment with a transmission electron microscope. Specifically, the projected area of the primary particles of the pigment is determined, and the corresponding circle equivalent diameter is calculated as the primary particle diameter of the pigment. In this specification, the average primary particle diameter is the arithmetic mean value of the primary particle diameters of 400 primary particles of the pigment. In addition, the primary particles of the pigment refer to independent particles that are not aggregated.
The crystallite size of the pigment, determined from the half-width of a peak derived from any crystal plane in an X-ray diffraction spectrum obtained using CuKα radiation as an X-ray source, is preferably 0.1 nm to 100 nm, more preferably 0.5 nm to 50 nm, even more preferably 1 nm to 30 nm, and particularly preferably 5 nm to 25 nm.

Green colorants include phthalocyanine compounds and squarylium compounds, and are preferably phthalocyanine compounds. The green colorant is preferably a pigment. Specific examples of green colorants include green pigments such as C.I. Pigment Green 7, 10, 36, 37, 58, 59, 62, 63, 64, 65, and 66. Green colorants may also include compounds described in paragraphs 0143 to 0149 of WO 2022/085485, aluminum phthalocyanine compounds described in JP 2020-070426 A, and diarylmethane compounds described in JP 2020-504758 A.

The green colorant is preferably C.I. Pigment Green 7, 36, 58, 59, 62, or 63, and more preferably C.I. Pigment Green 7, 36, 58, or 59.

Examples of the red colorant include diketopyrrolopyrrole compounds, anthraquinone compounds, azo compounds, naphthol compounds, azomethine compounds, xanthene compounds, quinacridone compounds, perylene compounds, and thioindigo compounds, and are preferably diketopyrrolopyrrole compounds, anthraquinone compounds, and azo compounds, and more preferably diketopyrrolopyrrole compounds. The red colorant is preferably a pigment. Specific examples of the red colorant include C.I. (Color Index) Pigment Red 1, 2, 3, 4, 5, 6, 7, 9, 10, 14, 17, 22, 23, 31, 38, 41, 48: 1, 48: 2, 48: 3, 48: 4, 49, 49: 1, 49: 2, 52: 1, 52: 2, 53: 1, 57: 1, 60: 1, 63: 1, 66, 67, 81: 1, 81: 2, 81: 3, 83, 88, 90, 105, 112, 119, 122, 123, 144, 146, 149, Examples of red pigments include 150, 155, 166, 168, 169, 170, 171, 172, 175, 176, 177, 178, 179, 184, 185, 187, 188, 190, 200, 202, 206, 207, 208, 209, 210, 216, 220, 224, 226, 242, 246, 254, 255, 264, 269, 270, 272, 279, 291, 294, 295, 296, and 297. In addition, the compound described in paragraph 0034 of WO 2022/085485 can also be used as a red colorant.
As a red colorant, Lumogen F Orange 240 (manufactured by BASF, red pigment, perylene pigment) can also be used.

The red colorant is preferably C.I. Pigment Red 122, 177, 179, 254, 255, 264, 269, 272, or 291, and more preferably C.I. Pigment Red 254, 264, or 272.

Examples of the yellow colorant include azo compounds, azomethine compounds, isoindoline compounds, pteridine compounds, quinophthalone compounds, and perylene compounds. The yellow colorant is preferably a pigment, more preferably an azo pigment, an azomethine pigment, an isoindoline pigment, a pteridine pigment, a quinophthalone pigment, or a perylene pigment, and more preferably an azo pigment or an azomethine pigment. Specific examples of the yellow colorant include C.I. Pigment Yellow 1, 2, 3, 4, 5, 6, 10, 11, 12, 13, 14, 15, 16, 17, 18, 20, 24, 31, 32, 34, 35, 35:1, 36, 36:1, 37, 37:1, 40, 42, 43, 53, 55, 60, 61, 62, 63, 65, 73, 74, 77, 81, 83, 86, 93, 94, 95, 97, 98, 100, 101, 104, 106, 108, 109, 110, 113, 114, 115, 116, 117, 118, 119, 120, 123, 125 , 126, 127, 128, 129, 137, 138, 139, 147, 148, 150, 151, 152, 153, 154, 155, 156, 161, 162, 164, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 179, 180, 181, 182, 185, 187, 188, 193, 194, 199, 213, 214, 215, 228, 231, 232, 233, 234, 235, 236 and the like.
Furthermore, as a yellow colorant, an azobarbituric acid nickel complex having the following structure can also be used.

In addition, the compounds described in paragraphs 0031 to 0033 of WO 2022/085485 can also be used as yellow colorants.

The yellow colorant is preferably C.I. Pigment Yellow 117, 129, 138, 139, 150, or 185.

Orange colorants include orange pigments such as C.I. Pigment Orange 2, 5, 13, 16, 17:1, 31, 34, 36, 38, 43, 46, 48, 49, 51, 52, 55, 59, 60, 61, 62, 64, 71, and 73.

Examples of purple colorants include purple pigments such as C.I. Pigment Violet 1, 19, 23, 27, 32, 37, 42, 60, and 61.

Examples of blue colorants include C.I. Pigment Blue 1, 2, 15, 15:1, 15:2, 15:3, 15:4, 15:6, 16, 22, 29, 60, 64, 66, 79, 80, 87, and 88. Aluminum phthalocyanine compounds having phosphorus atoms can also be used as blue colorants. Specific examples include the compounds described in paragraphs 0022 to 0030 of JP-A No. 2012-247591 and paragraph 0047 of JP-A No. 2011-157478.

Dyes can also be used as chromatic colorants. There are no particular limitations on the dyes, and any known dyes can be used. Examples include pyrazole azo dyes, anilino azo dyes, triarylmethane dyes, anthraquinone dyes, anthrapyridone dyes, benzylidene dyes, oxonol dyes, pyrazolotriazole azo dyes, pyridone azo dyes, cyanine dyes, phenothiazine dyes, pyrrolopyrazole azomethine dyes, xanthene dyes, phthalocyanine dyes, benzopyran dyes, indigo dyes, and pyrromethene dyes.

　A dye polymer can also be used as the chromatic colorant. The dye polymer is preferably a dye dissolved in an organic solvent before use. The dye polymer may also form particles. When the dye polymer is in the form of particles, it is usually used in a state of being dispersed in a solvent. A dye polymer in a particulate state can be obtained, for example, by emulsion polymerization, and specific examples of the compound and manufacturing method described in JP-A-2015-214682 include the compound described in paragraph 0048 of WO 2022/085485. As the dye polymer, a compound described in WO 2022/085485, paragraph 0048 can also be used.

Chromatic colorants include diarylmethane compounds described in JP-T-2020-504758, triarylmethane dye polymers described in Korean Patent Publication No. 10-2020-0028160, xanthene compounds described in JP-A-2020-117638, phthalocyanine compounds described in WO 2020/174991, isoindoline compounds or salts thereof described in JP-A-2020-160279, compounds represented by formula (1) described in Korean Patent Publication No. 10-2020-0069442, compounds represented by formula (1) described in Korean Patent Publication No. 10-2020-0069730, and compounds represented by formula (1) described in Korean Patent Publication No. 10-2020-0069730. Compounds represented by formula (1) described in Korean Patent Publication No. 10-2020-0069070, compounds represented by formula (1) described in Korean Patent Publication No. 10-2020-0069067, compounds represented by formula (1) described in Korean Patent Publication No. 10-2020-0069062, halogenated zinc phthalocyanine pigments described in Japanese Patent No. 6809649, isoindoline compounds described in JP-A-2020-180176, phenothiazine compounds described in JP-A-2021-187913, quinophthalone compounds represented by formula 1 of Korean Patent Publication No. 10-2020-0030759, Korean Patent Publication No. 10-2020-00617 Polymer dyes described in JP-A-93, colorants described in JP-A-2022-029701, isoindoline compounds described in WO 2022/014635, aluminum phthalocyanine compounds described in WO 2022/024926, compounds described in JP-A-2022-045895, compounds described in WO 2022/050051, compounds described in JP-A-2020-090676, compounds described in JP-A-2020-055956, compounds described in JP-A-2021-031681, compounds described in JP-A-2022-056354, compounds described in US 2021/0355327, Compounds described in International Publication No. 2022/065357, compounds described in JP 2020-045436 A, compounds described in Korean Patent Publication No. 10-2021-0146726 A, compounds described in JP 2018-178039 A, compounds described in Chinese Patent Application Publication No. 113881244 A, compounds described in Chinese Patent Application Publication No. 113881245 A, compounds described in Chinese Patent Application Publication No. 113881246 A, compounds described in Japanese Patent Application Publication No. 2022-104822 A, compounds described in Japanese Patent Application Publication No. 2022-096701 A, compounds described in Japanese Patent Application Publication No. 2020-023652 A, and the like can be used. The chromatic colorant may be a rotaxane, and the dye skeleton may be used in the cyclic structure of the rotaxane, may be used in the rod-shaped structure, or may be used in both structures.

Two or more chromatic colorants may be used in combination. When two or more chromatic colorants are used in combination, the combination of two or more chromatic colorants may form a black color.

The black colorant is not particularly limited, and any known black colorant can be used. For example, examples of inorganic black colorants include carbon black, titanium black, zirconium oxynitride, graphite, etc., with carbon black, titanium black, or zirconium oxynitride being preferred, and titanium black or zirconium oxynitride being more preferred. Titanium black is a black particle containing titanium atoms, and low-order titanium oxide or titanium oxynitride is preferred. Titanium black can be surface-modified as necessary for the purpose of improving dispersibility, suppressing aggregation, etc. For example, the surface of titanium black can be coated with silicon oxide, titanium oxide, germanium oxide, aluminum oxide, magnesium oxide, or zirconium oxide. It is also possible to treat it with a water-repellent substance as shown in JP-A-2007-302836. Color Index (C.I.) Pigment Black 1, 7 can also be used as a black colorant. It is preferable that both the primary particle size and the average primary particle size of the individual particles of titanium black are small. Specifically, it is preferable that the average primary particle size is 10 to 45 nm. Titanium black can also be used as a dispersion. For example, a dispersion containing titanium black particles and silica particles, and in which the content ratio of Si atoms to Ti atoms in the dispersion is adjusted to a range of 0.20 to 0.50, can be mentioned. For the above dispersion, the description in paragraphs 0020 to 0105 of JP 2012-169556 A can be referred to, and the contents thereof are incorporated herein. Examples of commercially available titanium black products include Titanium Black 10S, 12S, 13R, 13M, 13M-C, 13R-N, and 13M-T (product names: manufactured by Mitsubishi Materials Corporation), Tilack D (product name: manufactured by Ako Kasei Co., Ltd.), and the like. Examples of organic black colorants include bisbenzofuranone compounds, azomethine compounds, perylene compounds, and azo compounds, and bisbenzofuranone compounds and perylene compounds are preferred. Examples of bisbenzofuranone compounds include those described in JP-T-2010-534726, JP-T-2012-515233, JP-T-2012-515234, WO 2014/208348, and JP-T-2015-525260, and are available, for example, as "Irgaphor Black" manufactured by BASF. Examples of perylene compounds include C.I. Pigment Black 31 and 32. Examples of azomethine compounds include those described in JP-A-01-170601 and JP-A-02-034664, and are available, for example, as "Chromofine Black A1103" manufactured by Dainichi Seika Chemicals Co., Ltd. In addition, perylene black (such as Lumogen Black FK4280) and Paliogen Black S0084 described in paragraphs 0016 to 0020 of JP2017-226821A may be used as the organic black colorant.

The curable composition according to the present disclosure may contain one colorant alone or two or more colorants. When two or more colorants are used, the total amount of the colorants is preferably within the following range.
From the viewpoint of further exerting the effects of the present disclosure, the content of the colorant is preferably 10% by mass to 75% by mass based on the total solid content of the curable composition. The upper limit is more preferably 70% by mass or less, and even more preferably 65% by mass or less. The lower limit is more preferably 20% by mass or more, even more preferably 30% by mass or more, and particularly preferably 60% by mass or more.

<Resin>
The curable composition according to the present disclosure can contain a resin.
The curable composition according to the present disclosure can use a resin as the radical curable compound. It is preferable to use a radical curable compound that contains at least a resin. The resin is blended, for example, for dispersing pigments and the like in the curable composition or for use as a binder. Note that a resin that is mainly used to disperse pigments and the like in the curable composition is also called a dispersant. However, such uses of the resin are only examples, and the resin can also be used for purposes other than such uses.
Incidentally, a resin having a radically polymerizable group also corresponds to a radically curable compound.
Moreover, the curable composition according to the present disclosure more preferably further contains a resin other than the radically curable compound.

The weight average molecular weight of the resin is preferably 3,000 to 2,000,000. The upper limit is preferably 1,000,000 or less, and more preferably 500,000 or less. The lower limit is preferably 4,000 or more, and more preferably 5,000 or more.

The resins include (meth)acrylic resins, epoxy resins, ene-thiol resins, polycarbonate resins, polyether resins, polyarylate resins, polysulfone resins, polyethersulfone resins, polyphenylene resins, polyarylene ether phosphine oxide resins, polyimide resins, polyamide resins, polyamideimide resins, polyolefin resins, cyclic olefin resins, polyester resins, styrene resins, vinyl acetate resins, polyvinyl alcohol resins, polyvinyl acetal resins, polyurethane resins, and polyurea resins. One of these resins may be used alone, or two or more may be mixed and used. As the cyclic olefin resin, norbornene resin is preferred from the viewpoint of improving heat resistance. Commercially available norbornene resins include, for example, the ARTON series (e.g., ARTON F4520) manufactured by JSR Corporation. In addition, examples of the resin include the resins described in the examples of WO 2016/088645, the resins described in JP 2017-057265 A, the resins described in JP 2017-032685 A, the resins described in JP 2017-075248 A, the resins described in JP 2017-066240 A, the resins described in JP 2017-167513 A, the resins described in JP 2017-173787 A, and the resins described in paragraphs 0041 to 0060 of JP 2017-206689 A. Resins described in paragraphs 0022 to 0071 of JP 2018-010856 A, blocked polyisocyanate resins described in JP 2016-222891 A, resins described in JP 2020-122052 A, resins described in JP 2020-111656 A, resins described in JP 2020-139021 A, resins containing a structural unit having a ring structure in the main chain and a structural unit having a biphenyl group in the side chain described in JP 2017-138503 A can also be used. In addition, resins having a fluorene skeleton can also be preferably used as the resin. For resins having a fluorene skeleton, the description in U.S. Patent Application Publication No. 2017/0102610 can be referred to, and the contents of this specification are incorporated herein. In addition, as the resin, the resin described in paragraphs 0199 to 0233 of JP 2020-186373 A, the alkali-soluble resin described in JP 2020-186325 A, the resin represented by formula (1) described in Korean Patent Publication No. 10-2020-0078339 A, the copolymer containing an epoxy group and an acid group described in WO 2022/030445 A, and the compound described in JP 2018-135514 A can also be used.

It is preferable to use a resin having an acid group as the resin. Examples of the acid group include a carboxyl group, a phosphate group, a sulfo group, and a phenolic hydroxyl group. These acid groups may be of only one type, or of two or more types. The resin having an acid group can be used, for example, as an alkali-soluble resin. The acid value of the resin having an acid group is preferably 30 to 500 mgKOH/g. The lower limit is preferably 50 mgKOH/g or more, and more preferably 70 mgKOH/g or more. The upper limit is preferably 400 mgKOH/g or less, more preferably 200 mgKOH/g or less, even more preferably 150 mgKOH/g or less, and most preferably 120 mgKOH/g or less.

The resin may also be the compound described in paragraphs 0056 to 0059 of WO 2022/085485.

As the resin, it is also preferable to use a resin having a polymerizable group. Examples of the polymerizable group include an ethylenically unsaturated group and a cyclic ether group. Among them, from the viewpoint of sensitivity, it is preferable to use a resin having a (meth)acryloyl group, an epoxy group, or an oxetanyl group.

Furthermore, as the resin, a resin having at least one repeating unit (hereinafter also referred to as repeating unit Ep) selected from the repeating units represented by formula (Ep-1) and the repeating units represented by formula (Ep-2) can be used (hereinafter also referred to as resin Ep). The above resin Ep may contain only one of the repeating units represented by formula (Ep-1) and the repeating units represented by formula (Ep-2), or may contain both the repeating units represented by formula (Ep-1) and the repeating units represented by formula (Ep-2). When both repeating units are contained, the ratio of the repeating units represented by formula (Ep-1) to the repeating units represented by formula (Ep-2) is preferably 5:95 to 95:5 in molar ratio, more preferably 10:90 to 90:10, and even more preferably 20:80 to 80:20.

In formulae (Ep-1) and (Ep-2), L ¹ represents a single bond or a divalent linking group, and R ¹ represents a hydrogen atom or a substituent. Examples of the substituent represented by R ¹ include an alkyl group and an aryl group, and an alkyl group is preferable. The number of carbon atoms of the alkyl group is preferably 1 to 10, more preferably 1 to 5, and even more preferably 1 to 3. R ¹ is preferably a hydrogen atom or a methyl group. Examples of the divalent linking group represented by L ¹ include an alkylene group (preferably an alkylene group having 1 to 12 carbon atoms), an arylene group (preferably an arylene group having 6 to 20 carbon atoms), -NH-, -SO-, -SO ₂ -, -CO-, -O-, -COO-, -OCO-, -S-, and a group formed by combining two or more of these. The alkylene group may be linear, branched, or cyclic, and is preferably linear or branched. In addition, the alkylene group may have a substituent or may be unsubstituted. Examples of the substituent include a hydroxy group and an alkoxy group.

The content of the repeating unit Ep in the resin Ep is preferably 1 mol% to 100 mol% of all repeating units in the resin Ep. The upper limit is more preferably 90 mol% or less, and even more preferably 80 mol% or less. The lower limit is more preferably 2 mol% or more, and even more preferably 3 mol% or more.

The resin Ep may have other repeating units in addition to the repeating unit Ep. Examples of the other repeating units include a repeating unit having an acid group and a repeating unit having an ethylenically unsaturated group.

Examples of the acid group include a phenolic hydroxy group, a carboxyl group, a sulfo group, and a phosphate group, with a phenolic hydroxy group or a carboxyl group being preferred, and a carboxyl group being more preferred.

Examples of ethylenically unsaturated groups include vinyl groups, styrene groups, (meth)allyl groups, and (meth)acryloyl groups.

When the resin Ep contains a repeating unit having an acid group, the content of the repeating unit having an acid group in the resin Ep is preferably 5 mol% to 85 mol% of all repeating units of the resin Ep. The upper limit is more preferably 60 mol% or less, and even more preferably 40 mol% or less. The lower limit is more preferably 8 mol% or more, and even more preferably 10 mol% or more.

When the resin Ep contains a repeating unit having an ethylenically unsaturated group, the content of the repeating unit having an ethylenically unsaturated group in the resin Ep is preferably 1 mol% to 65 mol% of all repeating units of the resin Ep. The upper limit is more preferably 45 mol% or less, and even more preferably 30 mol% or less. The lower limit is more preferably 2 mol% or more, and even more preferably 3 mol% or more.

The resin Ep preferably further contains a repeating unit having an aromatic hydrocarbon ring. The aromatic hydrocarbon ring is preferably a benzene ring or a naphthalene ring, and is preferably a benzene ring. The aromatic hydrocarbon ring may have a substituent. Examples of the substituent include an alkyl group. When the resin having a cyclic ether group contains a repeating unit having an aromatic hydrocarbon ring, the content of the repeating unit having an aromatic hydrocarbon ring is preferably 1 mol% to 65 mol% of the total repeating units of the resin having a cyclic ether group. The upper limit is more preferably 45 mol% or less, and even more preferably 30 mol% or less. The lower limit is more preferably 2 mol% or more, and even more preferably 3 mol% or more. Examples of the repeating unit having an aromatic hydrocarbon ring include repeating units derived from monofunctional polymerizable compounds having an aromatic hydrocarbon ring, such as vinyl toluene and benzyl (meth)acrylate.

As the resin, it is also preferable to use a resin containing a repeating unit derived from a compound represented by formula (X).

In the formula, R ¹ represents a hydrogen atom or a methyl group, R ²¹ and R ²² each independently represent an alkylene group, and n represents an integer of 0 to 15. The number of carbon atoms in the alkylene group represented by R ²¹ and R ²² is preferably 1 to 10, more preferably 1 to 5, even more preferably 1 to 3, and particularly preferably 2 or 3. n represents an integer of 0 to 15, preferably an integer of 0 to 5, more preferably an integer of 0 to 4, and even more preferably an integer of 0 to 3.

Examples of the compound represented by formula (X) include ethylene oxide or propylene oxide modified (meth)acrylate of paracumylphenol. Commercially available products include Aronix M-110 (manufactured by Toagosei Co., Ltd.).

As the resin, it is also preferable to use a resin having an aromatic carboxyl group (hereinafter, also referred to as resin Ac). In resin Ac, the aromatic carboxyl group may be contained in the main chain of the repeating unit, or may be contained in the side chain of the repeating unit. It is preferable that the aromatic carboxyl group is contained in the main chain of the repeating unit. In this specification, an aromatic carboxyl group refers to a group having a structure in which one or more carboxyl groups are bonded to an aromatic ring. In the aromatic carboxyl group, the number of carboxyl groups bonded to the aromatic ring is preferably 1 to 4, and more preferably 1 to 2.

The resin Ac is preferably a resin containing at least one repeating unit selected from the repeating units represented by formula (Ac-1) and the repeating units represented by formula (Ac-2).

In formula (Ac-1), Ar ¹ represents a group containing an aromatic carboxyl group, L ¹ represents --COO-- or CONH--, and L ² represents a divalent linking group.
In formula (Ac-2), Ar ¹⁰ represents a group containing an aromatic carboxyl group, L ¹¹ represents --COO-- or CONH--, L ¹² represents a trivalent linking group, and P ¹⁰ represents a polymer chain.

In formula (Ac-1), examples of the group containing an aromatic carboxyl group represented by Ar ¹ include a structure derived from an aromatic tricarboxylic acid anhydride, a structure derived from an aromatic tetracarboxylic acid anhydride, etc. Examples of the aromatic tricarboxylic acid anhydride and aromatic tetracarboxylic acid anhydride include compounds having the following structures.

In the above formula, Q ¹ represents a single bond, —O—, —CO—, —COOCH ₂ CH ₂ OCO—, —SO ₂ —, —C(CF ₃ ) ₂ —, a group represented by the following formula (Q-1) or a group represented by the following formula (Q-2).

The group containing an aromatic carboxyl group represented by Ar ¹ may have a polymerizable group. The polymerizable group is preferably an ethylenically unsaturated group or a cyclic ether group, and more preferably an ethylenically unsaturated group.
Specific examples of the group containing an aromatic carboxyl group represented by Ar ¹ include a group represented by formula (Ar-11), a group represented by formula (Ar-12), and a group represented by formula (Ar-13).

In formula (Ar-11), n1 represents an integer of 1 to 4, preferably 1 or 2, and more preferably 2.
In formula (Ar-12), n2 represents an integer of 1 to 8, preferably an integer of 1 to 4, more preferably 1 or 2, and even more preferably 2.
In formula (Ar-13), n3 and n4 each independently represent an integer of 0 to 4, and are preferably an integer of 0 to 2, more preferably 1 or 2, and further preferably 1. However, at least one of n3 and n4 is an integer of 1 or more.
In formula (Ar-13), Q ¹ represents a single bond, —O—, —CO—, —COOCH ₂ CH ₂ OCO—, —SO ₂ —, —C(CF ₃ ) ₂ —, a group represented by the above formula (Q-1) or a group represented by the above formula (Q-2).
In formulae (Ar-11) to (Ar-13), *1 represents the bonding position to ^L1 .

In formula (Ac-1), ^L1 represents --COO-- or CONH--, and preferably represents --COO--.

In formula (Ac-1), the divalent linking group represented by L ² includes an alkylene group, an arylene group, -O-, -CO-, -COO-, -OCO-, -NH-, -S-, and a group combining two or more of these. The number of carbon atoms in the alkylene group is preferably 1 to 30, more preferably 1 to 20, and even more preferably 1 to 15. The alkylene group may be linear, branched, or cyclic. The number of carbon atoms in the arylene group is preferably 6 to 30, more preferably 6 to 20, and even more preferably 6 to 10. The alkylene group and the arylene group may have a substituent. Examples of the substituent include a hydroxy group. The divalent linking group represented by L ² is preferably a group represented by -L ^2a -O-. L ^2a may be an alkylene group; an arylene group; a group combining an alkylene group and an arylene group; a group combining at least one selected from an alkylene group and an arylene group with at least one selected from -O-, -CO-, -COO-, -OCO-, -NH- and S-, and is preferably an alkylene group. The number of carbon atoms in the alkylene group is preferably 1 to 30, more preferably 1 to 20, and even more preferably 1 to 15. The alkylene group may be linear, branched, or cyclic. The alkylene group and the arylene group may have a substituent. Examples of the substituent include a hydroxy group.

The aromatic carboxyl group-containing group represented by Ar ¹⁰ in formula (Ac-2) has the same meaning as Ar ¹ in formula (Ac-1), and preferred embodiments are also the same.

In formula (Ac-2), L ¹¹ represents —COO— or CONH—, and preferably represents —COO—.

In formula (Ac-2), the trivalent linking group represented by L ¹² includes a hydrocarbon group, -O-, -CO-, -COO-, -OCO-, -NH-, -S-, and a group combining two or more of these. Examples of the hydrocarbon group include an aliphatic hydrocarbon group and an aromatic hydrocarbon group. The carbon number of the aliphatic hydrocarbon group is preferably 1 to 30, more preferably 1 to 20, and even more preferably 1 to 15. The aliphatic hydrocarbon group may be linear, branched, or cyclic. The carbon number of the aromatic hydrocarbon group is preferably 6 to 30, more preferably 6 to 20, and even more preferably 6 to 10. The hydrocarbon group may have a substituent. Examples of the substituent include a hydroxyl group. The trivalent linking group represented by L ¹² is preferably a group represented by formula (L12-1), and more preferably a group represented by formula (L12-2).

In formula (L12-1), L ^12b represents a trivalent linking group, X ¹ represents S, *1 represents the bonding position to L ¹¹ in formula (Ac-2), and *2 represents the bonding position to P ¹⁰ in formula (Ac-2). Examples of the trivalent linking group represented by L ^12b include a hydrocarbon group; and a group in which a hydrocarbon group is combined with at least one selected from -O-, -CO-, -COO-, -OCO-, -NH-, and -S-, and the like. A hydrocarbon group or a group in which a hydrocarbon group is combined with -O- is preferred.

In formula (L12-2), L ^12c represents a trivalent linking group, X ¹ represents S, *1 represents the bonding position to L ¹¹ in formula (Ac-2), and *2 represents the bonding position to P ¹⁰ in formula (Ac-2). Examples of the trivalent linking group represented by L ^12c include a hydrocarbon group; and a group in which a hydrocarbon group is combined with at least one selected from -O-, -CO-, -COO-, -OCO-, -NH-, and -S-, and the like, with a hydrocarbon group being preferred.

In formula (Ac-2), P ¹⁰ represents a polymer chain. The polymer chain represented by P ¹⁰ preferably has at least one repeating unit selected from poly(meth)acrylic repeating units, polyether repeating units, polyester repeating units, and polyol repeating units. The weight average molecular weight of the polymer chain P ¹⁰ is preferably 500 to 20,000. The lower limit is more preferably 1,000 or more. The upper limit is more preferably 10,000 or less, even more preferably 5,000 or less, and particularly preferably 3,000 or less. When the weight average molecular weight of P ¹⁰ is within the above range, the dispersibility of the pigment in the composition is good. When the resin having an aromatic carboxyl group is a resin having a repeating unit represented by formula (Ac-2), this resin is preferably used as a dispersant.

The polymer chain represented by P ¹⁰ may contain a polymerizable group. The polymerizable group may be an ethylenically unsaturated group.

The curable composition according to the present disclosure preferably contains a resin as a dispersant. Examples of dispersants include acidic dispersants (acidic resins) and basic dispersants (basic resins). Here, the acidic dispersant (acidic resin) refers to a resin in which the amount of acid groups is greater than the amount of basic groups. As the acidic dispersant (acidic resin), a resin in which the amount of acid groups is 70 mol% or more is preferable when the total amount of the acid groups and the amount of the basic groups is 100 mol%. The acid group possessed by the acidic dispersant (acidic resin) is preferably a carboxyl group. The acid value of the acidic dispersant (acidic resin) is preferably 10 mgKOH/g to 105 mgKOH/g. In addition, the basic dispersant (basic resin) refers to a resin in which the amount of basic groups is greater than the amount of acid groups. As the basic dispersant (basic resin), a resin in which the amount of basic groups is greater than 50 mol% is preferable when the total amount of the acid groups and the amount of the basic groups is 100 mol%.
The basic group contained in the basic dispersant is preferably an amino group.

The resin used as the dispersant is preferably a graft polymer. For details of the graft polymer, refer to paragraphs 0025 to 0094 of JP2012-255128A, the contents of which are incorporated herein by reference.
From the viewpoint of dispersion stability, it is preferable that the resin is a graft polymer having a graft chain, the graft chain includes at least one type selected from the group consisting of a polyether chain, a polyester chain, and a polyacrylic chain, and the weight average molecular weight of the graft chain is 1,000 or more.

The resin used as the dispersant is preferably a polyimine-based dispersant containing nitrogen atoms in at least one of the main chain and side chain. The polyimine-based dispersant is preferably a resin having a main chain with a partial structure having a functional group with a pKa of 14 or less, a side chain with 40 to 10,000 atoms, and having a basic nitrogen atom in at least one of the main chain and side chain. There are no particular restrictions on the basic nitrogen atom, so long as it is a nitrogen atom that exhibits basicity. For details of polyimine-based dispersants, please refer to the description in paragraphs 0102 to 0166 of JP 2012-255128 A, the contents of which are incorporated herein by reference.

The resin used as the dispersant is preferably one having a structure in which multiple polymer chains are bonded to a core portion. Examples of such resins include dendrimers (including star-shaped polymers). Specific examples of dendrimers include polymer compounds C-1 to C-31 described in paragraphs 0196 to 0209 of JP 2013-043962 A.

The resin used as the dispersant is also preferably a resin containing a repeating unit having an ethylenically unsaturated group in a side chain. The content of the repeating unit having an ethylenically unsaturated group in a side chain is preferably 10 mol % or more, more preferably 10 mol % to 80 mol %, and even more preferably 20 mol % to 70 mol %, of all repeating units of the resin.
As a resin having an oxetane group, for example, a resin described in WO 2021/182268 or WO 2021/187257 can be used.

Moreover, the resin used as the dispersant is preferably a resin containing an oxetane group on the side chain, and more preferably a resin containing a repeating unit having an oxetane group on the side chain.
Furthermore, the resin containing an oxetane group in the side chain is preferably a graft polymer.
Suitable examples of the resin containing an oxetane group in a side chain include those described in the Examples below. The content of repeating units having an oxetane group in a side chain in the above resin is preferably 10 mol % or more, more preferably 10 mol % to 80 mol %, and even more preferably 20 mol % to 70 mol %, of all repeating units in the resin.

In addition, as dispersants, resins described in JP 2018-087939 A, block copolymers (EB-1) to (EB-9) described in paragraphs 0219 to 0221 of Japanese Patent No. 6,432,077 A, polyethyleneimine having a polyester side chain described in WO 2016/104803 A, block copolymers described in WO 2019/125940 A, block polymers having an acrylamide structural unit described in JP 2020-066687 A, block polymers having an acrylamide structural unit described in JP 2020-066688 A, dispersants described in WO 2016/104803 A, and the like can also be used.

As the dispersant, polyamic acid type dispersing resins and polyimide type dispersing resins can also be used. As such resins, dispersants described in WO 2022/019253, WO 2022/019254, and WO 2022/019255 can also be used.

Dispersants are also available as commercially available products, and specific examples include the Disperbyk series manufactured by BYK-Chemie (e.g., Disperbyk-111, 161, 2001, etc.), the Solsperse series manufactured by Lubrizol Japan Co., Ltd. (e.g., Solsperse 20000, 76500, etc.), and the Ajisper series manufactured by Ajinomoto Fine-Techno Co., Ltd. In addition, the products described in paragraph 0129 of JP 2012-137564 A and the products described in paragraph 0235 of JP 2017-194662 A can also be used as dispersants.

When the curable composition according to the present disclosure contains a resin as a radical curable compound, the content of the resin is preferably 1% by mass to 70% by mass based on the total solid content of the curable composition. The lower limit is more preferably 2% by mass or more, even more preferably 3% by mass or more, and particularly preferably 5% by mass or more. The upper limit is more preferably 65% by mass or less, and even more preferably 60% by mass or less.
The content of the resin having an acid group is preferably 1% by mass to 70% by mass based on the total solid content of the curable composition. The lower limit is more preferably 2% by mass or more, even more preferably 3% by mass or more, and particularly preferably 5% by mass or more. The upper limit is more preferably 65% by mass or less, and even more preferably 60% by mass or less.
The content of the alkali-soluble resin is preferably 1% by mass to 70% by mass based on the total solid content of the curable composition. The lower limit is more preferably 2% by mass or more, even more preferably 3% by mass or more, and particularly preferably 5% by mass or more. The upper limit is more preferably 65% by mass or less, and even more preferably 60% by mass or less.
When the curable composition according to the present disclosure contains a resin as a dispersant, the content of the resin as a dispersant is preferably 0.1% by mass to 30% by mass with respect to the total solid content of the curable composition. The upper limit is more preferably 25% by mass or less, and even more preferably 20% by mass or less. The lower limit is more preferably 0.5% by mass or more, and even more preferably 1% by mass or more. The content of the resin as a dispersant is preferably 1 part by mass to 100 parts by mass with respect to 100 parts by mass of the colorant. The upper limit is more preferably 80 parts by mass or less, even more preferably 70 parts by mass or less, and particularly preferably 60 parts by mass or less. The lower limit is more preferably 5 parts by mass or more, even more preferably 10 parts by mass or more, and particularly preferably 20 parts by mass or more.
The curable composition according to the present disclosure may contain only one type of resin, or may contain two or more types of resins. When two or more types of resins are contained, the total amount thereof is preferably within the above range.

<Solvent>
The curable composition according to the present disclosure preferably contains a solvent. Examples of the solvent include organic solvents. The type of solvent is not particularly limited as long as the solubility of each component and the coatability of the composition are satisfied. Examples of the organic solvent include ester-based solvents, ketone-based solvents, alcohol-based solvents, amide-based solvents, ether-based solvents, and hydrocarbon-based solvents. For details of these, reference can be made to paragraph 0223 of International Publication No. 2015/166779, the contents of which are incorporated herein by reference. In addition, ester-based solvents substituted with a cyclic alkyl group and ketone-based solvents substituted with a cyclic alkyl group can also be preferably used. Specific examples of organic solvents include polyethylene glycol monomethyl ether, dichloromethane, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, ethyl cellosolve acetate, ethyl lactate, diethylene glycol dimethyl ether, butyl acetate, methyl 3-methoxypropionate, 2-heptanone, 2-pentanone, 3-pentanone, 4-heptanone, cyclohexanone, 2-methylcyclohexanone, 3-methylcyclohexanone, 4-methylcyclohexanone, cycloheptanone, cyclooctanone, cyclohexyl acetate, cyclopentanone, ethyl carbitol acetate, butyl carbitol acetate, propylene glycol monomethyl ether, propylene glycol dimethyl ether, butyl acetate ... Examples of the ethylene glycol monomethyl ether acetate include 3-methoxy-N,N-dimethylpropanamide, 3-butoxy-N,N-dimethylpropanamide, propylene glycol diacetate, 3-methoxybutanol, methyl ethyl ketone, gamma butyrolactone, sulfolane, anisole, 1,4-diacetoxybutane, diethylene glycol monoethyl ether acetate, butane-1,3-diyl diacetate, dipropylene glycol methyl ether acetate, diacetone alcohol (also known as diacetone alcohol and 4-hydroxy-4-methyl-2-pentanone), 2-methoxypropyl acetate, 2-methoxy-1-propanol, and isopropyl alcohol. However, there are cases where it is better to reduce the amount of aromatic hydrocarbons (benzene, toluene, xylene, ethylbenzene, etc.) used as organic solvents for environmental reasons, etc. (for example, the amount can be 50 ppm (parts per million) by mass or less, 10 ppm by mass or less, or 1 ppm by mass or less, relative to the total amount of organic solvents).

In the present disclosure, it is preferable to use an organic solvent with a low metal content. The metal content of the organic solvent is preferably, for example, 10 parts per billion (ppb) by mass or less. If necessary, an organic solvent with a mass ppt (parts per trillion) level may be used, and such an organic solvent is provided, for example, by Toyo Gosei Co., Ltd. (The Chemical Daily, November 13, 2015).

Methods for removing impurities such as metals from organic solvents include, for example, distillation (molecular distillation, thin-film distillation, etc.) and filtration using a filter. The filter used for filtration preferably has a pore size of 10 μm or less, more preferably 5 μm or less, and even more preferably 3 μm or less. The filter material is preferably polytetrafluoroethylene, polyethylene, or nylon.

The organic solvent may contain isomers (compounds with the same number of atoms but different structures). In addition, the organic solvent may contain only one type of isomer, or multiple types of isomers.

The peroxide content in the organic solvent is preferably 0.8 mmol/L or less, and more preferably substantially free of peroxide.

The content of the solvent in the curable composition is preferably 10% by mass to 95% by mass, more preferably 20% by mass to 90% by mass, and even more preferably 30% by mass to 90% by mass.

In addition, from the viewpoint of environmental regulations, it is preferable that the curable composition according to the present disclosure is substantially free of environmentally regulated substances. In this disclosure, substantially free of environmentally regulated substances means that the content of environmentally regulated substances in the curable composition is 50 ppm by mass or less, preferably 30 ppm by mass or less, more preferably 10 ppm by mass or less, and particularly preferably 1 ppm by mass or less. Examples of environmentally regulated substances include benzene; alkylbenzenes such as toluene and xylene; and halogenated benzenes such as chlorobenzene. These substances are registered as environmentally regulated substances under the REACH (Registration Evaluation Authorization and Restriction of Chemicals) Regulations, the PRTR (Pollutant Release and Transfer Register) Law, the VOC (Volatile Organic Compounds) Regulations, etc., and their usage and handling methods are strictly regulated. These compounds may be used as solvents when producing each component used in the curable composition, and may be mixed into the curable composition as a residual solvent. From the viewpoint of human safety and environmental consideration, it is preferable to reduce these substances as much as possible. As a method for reducing environmentally regulated substances, a method of reducing them by heating or reducing pressure in the system to a temperature above the boiling point of the environmentally regulated substance and distilling off the environmentally regulated substance from the system can be mentioned. In addition, when distilling off a small amount of environmentally regulated substances, it is useful to perform azeotropy with a solvent having a boiling point equivalent to that of the solvent in question in order to increase efficiency. In addition, when a radically polymerizable compound is contained, a polymerization inhibitor or the like may be added and then distilled off under reduced pressure in order to suppress the radical polymerization reaction from proceeding during distillation under reduced pressure and causing crosslinking between molecules. These distillation methods can be used at any stage, such as the stage of the raw materials, the stage of the product obtained by reacting the raw materials (for example, a resin solution or a polyfunctional monomer solution after polymerization), or the stage of the curable composition prepared by mixing these compounds.

<Pigment Derivatives>
The curable composition according to the present disclosure may contain a pigment derivative. The pigment derivative is used, for example, as a dispersing aid. Examples of the pigment derivative include a compound having a structure in which an acid group or a basic group is bonded to a pigment skeleton.

　Examples of the pigment skeletons that make up the pigment derivatives include a quinoline dye skeleton, a benzimidazolone dye skeleton, a benzisoindole dye skeleton, a benzothiazole dye skeleton, an iminium dye skeleton, a squarylium dye skeleton, a croconium dye skeleton, an oxonol dye skeleton, a pyrrolopyrrole dye skeleton, a diketopyrrolopyrrole dye skeleton, an azo dye skeleton, an azomethine dye skeleton, a phthalocyanine dye skeleton, a naphthalocyanine dye skeleton, an anthraquinone dye skeleton, a quinacridone dye skeleton, a dioxazine dye skeleton, a perinone dye skeleton, a perylene dye skeleton, a thioindigo dye skeleton, an isoindoline dye skeleton, an isoindolinone dye skeleton, a quinophthalone dye skeleton, an iminium dye skeleton, a dithiol dye skeleton, a triarylmethane dye skeleton, and a pyrromethene dye skeleton.

Examples of the acid group include a carboxyl group, a sulfo group, a phosphoric acid group, a boronic acid group, a carboxylic acid amide group, a sulfonic acid amide group, an imide acid group, and salts thereof. Examples of atoms or atomic groups constituting the salt include an alkali metal ion (Li ⁺ , Na ⁺ , K ⁺ , etc.), an alkaline earth metal ion (Ca ²⁺ , Mg ²⁺ , etc.), an ammonium ion, an imidazolium ion, a pyridinium ion, and a phosphonium ion. Examples of the carboxylic acid amide group include a group represented by -NHCOR ^X1 . Examples of the sulfonic acid amide group include a group represented by -NHSO ₂ R ^X2 . Examples of the imide acid group include a group represented by -SO ₂ NHSO ₂ R ^X3 , -CONHSO ₂ R ^X4 , -CONHCOR ^X5 , or SO ₂ NHCOR ^X6 , and more preferably -SO ₂ NHSO ₂ R ^X3 . R ^x1 to R ^x6 each independently represent an alkyl group or an aryl group. The alkyl group and aryl group represented by R ^x1 to R ^x6 may have a substituent. The substituent is preferably a halogen atom, and more preferably a fluorine atom.

Basic groups include amino groups, pyridinyl groups and their salts, salts of ammonium groups, and phthalimidomethyl groups. Atoms or atomic groups that make up the salts include hydroxide ions, halogen ions, carboxylate ions, sulfonate ions, and phenoxide ions.

The pigment derivative may be a pigment derivative having excellent visible transparency (hereinafter, also referred to as a transparent pigment derivative). The maximum molar absorption coefficient (εmax) of the transparent pigment derivative in the wavelength region of 400 nm to 700 nm is preferably 3,000 L mol ^-1 cm- ¹ or less, more preferably 1,000 L mol ^-1 cm ^-1 or less, and even more preferably 100 L mol ^-1 cm ^-1 or less. The lower limit of εmax is, for example, 1 L mol ^-1 cm- ¹ or more, and may be 10 L mol ^-1 cm ^-1 or more.

Specific examples of pigment derivatives include the compounds described in paragraph 0124 of WO 2022/085485, the benzimidazolone compounds or salts thereof described in JP 2018-168244 A, and the compounds having an isoindoline skeleton described in general formula (1) of Japanese Patent No. 6996282.

The content of the pigment derivative is preferably 1 to 30 parts by mass, and more preferably 3 to 20 parts by mass, relative to 100 parts by mass of the colorant. The total content of the pigment derivative and the colorant is preferably 35% by mass or more, more preferably 40% by mass or more, even more preferably 45% by mass or more, and particularly preferably 50% by mass or more, relative to the total solid content of the curable composition. The upper limit is preferably 70% by mass or less, and more preferably 65% by mass or less. Only one type of pigment derivative may be used, or two or more types may be used in combination.

<Polyalkyleneimine>
The curable composition according to the present disclosure may also contain a polyalkyleneimine. The polyalkyleneimine is used, for example, as a dispersing aid for pigments. The dispersing aid is a material for enhancing the dispersibility of the pigment in the curable composition. The polyalkyleneimine is a polymer obtained by ring-opening polymerization of an alkyleneimine, and is a polymer having at least a secondary amino group. The polyalkyleneimine may contain a primary amino group or a tertiary amino group in addition to the secondary amino group. The polyalkyleneimine is preferably a polymer having a branched structure containing a primary amino group, a secondary amino group, and a tertiary amino group. The number of carbon atoms of the alkyleneimine is preferably 2 to 6, more preferably 2 to 4, even more preferably 2 or 3, and particularly preferably 2.

The molecular weight of the polyalkyleneimine is preferably 200 or more, more preferably 250 or more. The upper limit is preferably 100,000 or less, more preferably 50,000 or less, even more preferably 10,000 or less, and particularly preferably 2,000 or less. In addition, when the value of the molecular weight of the polyalkyleneimine can be calculated from the structural formula, the molecular weight of the polyalkyleneimine is the value calculated from the structural formula. On the other hand, when the molecular weight of the specific amine compound cannot be calculated from the structural formula or is difficult to calculate, the value of the number average molecular weight measured by the boiling point elevation method is used. In addition, when the molecular weight cannot be measured by the boiling point elevation method or is difficult to measure, the value of the number average molecular weight measured by the viscosity method is used. In addition, when the molecular weight cannot be measured by the viscosity method or is difficult to measure by the viscosity method, the value of the number average molecular weight in polystyrene equivalent value measured by the GPC (gel permeation chromatography) method is used.

The amine value of the polyalkyleneimine is preferably 5 mmol/g or more, more preferably 10 mmol/g or more, and even more preferably 15 mmol/g or more.

Specific examples of alkyleneimines include ethyleneimine, propyleneimine, 1,2-butyleneimine, and 2,3-butyleneimine, with ethyleneimine or propyleneimine being preferred, and ethyleneimine being more preferred. The polyalkyleneimine is particularly preferably polyethyleneimine. Furthermore, the polyethyleneimine preferably contains primary amino groups in an amount of 10 mol% or more, more preferably 20 mol% or more, and even more preferably 30 mol% or more, based on the total of the primary amino groups, secondary amino groups, and tertiary amino groups. Commercially available polyethyleneimines include Epomin SP-003, SP-006, SP-012, SP-018, SP-200, and P-1000 (all manufactured by Nippon Shokubai Co., Ltd.).

The content of the polyalkyleneimine in the total solid content of the curable composition is preferably 0.1% by mass to 5% by mass. The lower limit is more preferably 0.2% by mass or more, even more preferably 0.5% by mass or more, and particularly preferably 1% by mass or more. The upper limit is more preferably 4.5% by mass or less, even more preferably 4% by mass or less, and particularly preferably 3% by mass or less. The content of the polyalkyleneimine is preferably 0.5 parts by mass to 20 parts by mass relative to 100 parts by mass of the pigment. The lower limit is more preferably 0.6 parts by mass or more, even more preferably 1 part by mass or more, and particularly preferably 2 parts by mass or more. The upper limit is more preferably 10 parts by mass or less, and even more preferably 8 parts by mass or less. Only one type of polyalkyleneimine may be used, or two or more types may be used. When two or more types are used, it is preferable that the total amount thereof is within the above range.

<Curing accelerator>
The curable composition according to the present disclosure may contain a curing accelerator. Examples of the curing accelerator include a thiol compound, a methylol compound, an amine compound, a phosphonium salt compound, an amidine salt compound, an amide compound, a base generator, an isocyanate compound, an alkoxysilane compound, and an onium salt compound. Specific examples of the curing accelerator include the compounds described in paragraph 0164 of WO 2022/085485.
The content of the curing accelerator in the total solid content of the curable composition is preferably 0.3 mass % to 8.9 mass %, and more preferably 0.8 mass % to 6.4 mass %.

<Infrared absorbent>
The curable composition according to the present disclosure may contain an infrared absorbing agent. For example, when an infrared transmission filter is formed using the curable composition according to the present disclosure, the wavelength of light transmitted through the film obtained by adding an infrared absorbing agent to the curable composition can be shifted to a longer wavelength side. The infrared absorbing agent is preferably a compound having a maximum absorption wavelength on the longer wavelength side than a wavelength of 700 nm. The infrared absorbing agent is preferably a compound having a maximum absorption wavelength in the range of more than 700 nm and not more than 1800 nm. In addition, the ratio A ¹ /A ² between the absorbance A ¹ at a wavelength of 500 nm of the infrared absorbing agent and the absorbance A ² at the maximum absorption wavelength is preferably 0.08 or less, more preferably 0.04 or less.

Examples of the infrared absorber include pyrrolopyrrole compounds, cyanine compounds, squarylium compounds, phthalocyanine compounds, naphthalocyanine compounds, quaterrylene compounds, merocyanine compounds, croconium compounds, oxonol compounds, iminium compounds, dithiol compounds, triarylmethane compounds, pyrromethene compounds, azomethine compounds, anthraquinone compounds, dibenzofuranone compounds, dithiolene metal complexes, metal oxides, and metal borides.
Specifically, the compounds described in paragraphs 0114 to 0121 of WO 2022/065215, the compounds described in paragraphs 0144 to 0146 of WO 2021/049441, the croconic acid compounds described in JP 2021-195515 A, the near infrared absorbing dyes described in JP 2022-022070 A, the croconium compounds described in WO 2019/021767 A, the compounds described in JP 2019-127549 A, and the compounds described in WO 2022/059619 A can also be used.

The content of the infrared absorber in the total solid content of the curable composition is preferably 1% by mass to 40% by mass. The lower limit is more preferably 2% by mass or more, even more preferably 5% by mass or more, and particularly preferably 10% by mass or more. The upper limit is more preferably 30% by mass or less, and even more preferably 25% by mass or less. The curable composition according to the present disclosure may contain only one type of infrared absorber, or may contain two or more types. When two or more types of infrared absorbers are contained, it is preferable that the total amount thereof is within the above range.

<Ultraviolet absorbing agent>
The curable composition according to the present disclosure may contain an ultraviolet absorber. Examples of ultraviolet absorbers include conjugated diene compounds, aminodiene compounds, salicylate compounds, benzophenone compounds, benzotriazole compounds, acrylonitrile compounds, hydroxyphenyltriazine compounds, indole compounds, and triazine compounds. Specific examples of such compounds include the compounds described in paragraph 0179 of International Publication No. 2022/085485. As the ultraviolet absorber, the reactive triazine ultraviolet absorber described in JP-A-2021-178918, the ultraviolet absorber described in JP-A-2022-007884, the compound described in KR1020220014454A, and the like can also be used.
The content of the ultraviolet absorber in the total solid content of the curable composition is preferably 0.01% by mass to 10% by mass, more preferably 0.01% by mass to 5% by mass. Only one type of ultraviolet absorber may be used, or two or more types may be used. When two or more types are used, the total amount thereof is preferably within the above range.

<Polymerization inhibitor>
The curable composition according to the present disclosure may contain a polymerization inhibitor. Examples of the polymerization inhibitor include 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-t-butylphenol), and N-nitrosophenylhydroxyamine salt (ammonium salt, cerium salt, etc.). Among them, p-methoxyphenol is preferred. The content of the polymerization inhibitor in the total solid content of the curable composition is preferably 0.0001% by mass to 5% by mass. The polymerization inhibitor may be one type or two or more types. In the case of two or more types, it is preferable that the total amount thereof is within the above range.

<Silane coupling agent>
The curable composition according to the present disclosure may contain a silane coupling agent. In the present disclosure, the silane coupling agent refers to a silane compound having a hydrolyzable group and other functional groups. The hydrolyzable group refers to a substituent that is directly bonded to a silicon atom and can generate a siloxane bond by at least one of a hydrolysis reaction and a condensation reaction. Examples of the hydrolyzable group include a halogen atom, an alkoxy group, and an acyloxy group, and an alkoxy group is preferred. That is, the silane coupling agent is preferably a compound having an alkoxysilyl group. Examples of functional groups other than the hydrolyzable group include a vinyl group, a (meth)allyl group, a (meth)acryloyl group, a mercapto group, an epoxy group, an oxetanyl group, an amino group, a ureido group, a sulfide group, an isocyanate group, and a phenyl group, and an amino group, a (meth)acryloyl group, and an epoxy group are preferred. Specific examples of the silane coupling agent include the compounds described in paragraph 0177 of WO 2022/085485 and the compounds described in JP-A 2019-183020.
The content of the silane coupling agent in the total solid content of the curable composition is preferably from 0.01% by mass to 15.0% by mass, and more preferably from 0.05% by mass to 10.0% by mass.
The silane coupling agent may be one type or two or more types. When two or more types are used, the total amount thereof is preferably within the above range.

<Surfactant>
The curable composition according to the present disclosure may contain a surfactant. As the surfactant, various surfactants such as fluorine-based surfactants, nonionic surfactants, cationic surfactants, anionic surfactants, and silicone-based surfactants may be used. The surfactant is preferably a silicone-based surfactant or a fluorine-based surfactant. For the surfactant, reference may be made to the surfactants described in paragraphs 0238 to 0245 of WO 2015/166779, the contents of which are incorporated herein by reference.

The fluorine content in the fluorosurfactant is preferably 3% to 40% by mass, more preferably 5% to 30% by mass, and particularly preferably 7% to 25% by mass. Fluorine surfactants with a fluorine content within this range are effective in terms of uniformity of the coating film thickness and liquid saving, and also have good solubility in the curable composition.

As fluorosurfactants, compounds described in paragraphs 0167 to 0173 of WO 2022/085485, fluorine-containing copolymers described in JP 2022-000494 A, etc. can also be used.

As a nonionic surfactant, the compounds described in paragraph 0174 of WO 2022/085485 can also be used.

Silicone surfactants include DOWSIL SH8400, SH8400 FLUID, FZ-2122, 67 Additive, 74 Additive, M Additive, SF 8419 OIL (all manufactured by Dow Toray Co., Ltd.), TSF-4300, TSF-4445, TSF-4460, and TSF-4452 (all manufactured by Momen Co., Ltd.). Examples include BYK-307, BYK-322, BYK-323, BYK-330, BYK-333, BYK-3760, and BYK-UV3510 (manufactured by BYK-Chemie), etc.

　Also, compounds with the following structure can be used as silicone surfactants.

The content of the surfactant in the total solid content of the curable composition is preferably 0.001% by mass to 5.0% by mass, and more preferably 0.005% by mass to 3.0% by mass. There may be only one type of surfactant, or two or more types. When there are two or more types, it is preferable that the total amount thereof is within the above range.

<Antioxidants>
The curable composition according to the present disclosure may contain an antioxidant. Examples of the antioxidant include phenolic compounds, phosphite compounds, and thioether compounds. As the phenolic compound, any phenolic compound known as a phenolic antioxidant may be used. A preferred phenolic compound is a hindered phenolic compound. A compound having a substituent at the site (ortho position) adjacent to the phenolic hydroxy group is preferred. As the above-mentioned substituent, a substituted or unsubstituted alkyl group having 1 to 22 carbon atoms is preferred. In addition, the antioxidant is also preferably a compound having a phenolic group and a phosphite group in the same molecule. In addition, a phosphorus-based antioxidant may also be suitably used as the antioxidant. Examples of phosphorus-based antioxidants include tris[2-[[2,4,8,10-tetrakis(1,1-dimethylethyl)dibenzo[d,f][1,3,2]dioxaphosphepin-6-yl]oxy]ethyl]amine, tris[2-[(4,6,9,11-tetra-tert-butyldibenzo[d,f][1,3,2]dioxaphosphepin-2-yl)oxy]ethyl]amine, and ethylbis(2,4-di-tert-butyl-6-methylphenyl)phosphite. Commercially available antioxidants include, for example, Adeka STAB AO-20, Adeka STAB AO-30, Adeka STAB AO-40, Adeka STAB AO-50, Adeka STAB AO-50F, Adeka STAB AO-60, Adeka STAB AO-60G, Adeka STAB AO-80, and Adeka STAB AO-330 (manufactured by ADEKA Corporation). In addition, the antioxidant may be a compound described in paragraphs 0023 to 0048 of Japanese Patent No. 6268967, a compound described in International Publication No. WO 2017/006600, a compound described in International Publication No. WO 2017/164024, or a compound described in Korean Patent Publication No. 10-2019-0059371. The content of the antioxidant in the total solid content of the curable composition is preferably 0.01% by mass to 20% by mass, and more preferably 0.3% by mass to 15% by mass. Only one type of antioxidant may be used, or two or more types may be used. When two or more types are used, it is preferable that the total amount thereof is in the above range.

<Chain Transfer Agent>
From the viewpoints of adhesion and adhesion to a substrate, the curable composition according to the present disclosure preferably further contains a chain transfer agent.
Examples of the chain transfer agent include a thiol compound (hereinafter also referred to as a "thiol-based chain transfer agent"), a thiocarbonylthio compound, and an aromatic α-methylalkenyl dimer. Thiol-based chain transfer agents are preferred because they make it easy to adjust the line width of the pattern even when used in a small amount.
In addition, the use of a thiol-based chain transfer agent can further improve sensitivity and adhesion to a substrate, reduce the amount of radical polymerization initiator used, and suppress the generation of residues in the cured product of the curable composition of the present disclosure.
The chain transfer agent is preferably a compound that is less colored.

- Thiol-based chain transfer agent -
The thiol chain transfer agent is a compound having one or more thiol groups, and is preferably a compound having two or more thiol groups. The upper limit of the number of thiol groups contained in the thiol chain transfer agent is preferably 20 or less, more preferably 15 or less, even more preferably 10 or less, particularly preferably 8 or less, and most preferably 6 or less. The lower limit of the number of thiol groups contained in the thiol chain transfer agent is preferably 3 or more. From the viewpoint of adhesion, it is particularly preferable that the thiol chain transfer agent is a compound having four thiol groups. The thiol chain transfer agent is preferably a thiol chain transfer agent in which the carbon to which the thiol group is bonded has a substituent, and more preferably a thiol chain transfer agent in which the carbon to which the thiol group is bonded has an alkyl group as a substituent.

It is also preferred that the thiol chain transfer agent is a compound derived from a polyfunctional alcohol.

The thiol chain transfer agent is preferably a compound represented by the following formula (SH-1).
L ¹ -(SH) _n formula (SH-1)
In the formula, SH represents a thiol group, ^L1 represents an n-valent group, and n represents an integer of 1 or more.

In formula (SH-1), examples of the n-valent group represented by L ¹ include a hydrocarbon group, a heterocyclic group, -O-, -S-, -NR-, -CO-, -COO-, -OCO-, -SO ₂ -, or a group consisting of a combination thereof. R represents a hydrogen atom, an alkyl group, or an aryl group, and is preferably a hydrogen atom. The hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. The aliphatic hydrocarbon group may be cyclic or noncyclic. The aliphatic hydrocarbon group may be a saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group. The hydrocarbon group may have a substituent or may not have a substituent. The cyclic aliphatic hydrocarbon group and the aromatic hydrocarbon group may be a monocyclic ring or a condensed ring. The heterocyclic group may be a monocyclic ring or a condensed ring. The heterocyclic group is preferably a 5-membered ring or a 6-membered ring. The heterocyclic group may be an aliphatic heterocyclic group or an aromatic heterocyclic group. Examples of heteroatoms constituting the heterocyclic group include a nitrogen atom, an oxygen atom, a sulfur atom, etc. The number of carbon atoms constituting ^L1 is preferably 3 to 100, and more preferably 6 to 50.

In formula (SH-1), n represents an integer of 1 or more. The upper limit of n is preferably 20 or less, more preferably 15 or less, even more preferably 10 or less, particularly preferably 8 or less, and most preferably 6 or less. The lower limit of n is preferably 2 or more, more preferably 3 or more. It is particularly preferable that n is 4.

Specific examples of thiol chain transfer agents include compounds with the following structure. Commercially available thiol chain transfer agents include PEMP (manufactured by SC Organic Chemical Co., Ltd.), Suncerer M (manufactured by Sanshin Chemical Industry Co., Ltd.), and Karenz MT BD1 (manufactured by Showa Denko K.K.).

-Thiocarbonylthio compounds-
The thiocarbonylthio compound is a compound having a thiocarbonylthio group (-S-C(=S)-) in the molecule, and examples thereof include bis(thiocarbonyl)disulfide compounds (compounds represented by formula (SC-1) below), dithioester compounds (compounds represented by formula (SC-2) below), trithiocarbonate compounds (compounds represented by formula (SC-3) below), dithiocarbamate compounds (compounds represented by formula (SC-4) below), and xanthate compounds (compounds represented by formula (SC-5) below).

In formulae (SC-1) to (SC-5), Z ¹ to Z ¹¹ each independently represent a substituent.

Examples of the substituents represented by Z ¹ to Z ¹¹ include an alkyl group, an aryl group, a heteroaryl group, -SR ^Z1 , -NR ^Z1 R ^Z2 , -NR ^Z1 -NR ^Z2 R ^Z3 , -COOR ^Z1 , -OCOR ^Z1 , -CONR ^Z1 R ^Z2 , -P(═O)(OR ^Z1 ) ₂ or -O-P(═O)R ^Z1 R ^Z2 (wherein R ^Z1 , R ^Z2 and R ^Z3 are each independently an alkyl group, an aryl group or a heteroaryl group), etc. Among the above groups, one or more hydrogen atoms bonded to the carbon atom may be substituted with a cyano group, a carboxyl group, etc.
The number of carbon atoms in the alkyl group is preferably 1 to 30, more preferably 1 to 15, and still more preferably 1 to 8. The alkyl group may be linear, branched, or cyclic, and is preferably linear or branched.
The aryl group preferably has 6 to 30 carbon atoms, more preferably 6 to 20 carbon atoms, and even more preferably 6 to 12 carbon atoms.
The heteroaryl group is preferably a monocyclic heteroaryl group or a heteroaryl group having 2 to 8 condensed rings, more preferably a monocyclic heteroaryl group or a heteroaryl group having 2 to 4 condensed rings. The number of heteroatoms constituting the ring of the heteroaryl group is preferably 1 to 3. The heteroatoms constituting the ring of the heteroaryl group are preferably nitrogen atoms, oxygen atoms, or sulfur atoms. The heteroaryl group is preferably a 5-membered or 6-membered ring. The number of carbon atoms constituting the ring of the heteroaryl group is preferably 3 to 30, more preferably 3 to 18, and even more preferably 3 to 12.

Specific examples of bis(thiocarbonyl) disulfide compounds include tetraethyl thiuram disulfide, tetramethyl thiuram disulfide, bis(n-octyl mercapto-thiocarbonyl) disulfide, bis(n-dodecyl mercapto-thiocarbonyl) disulfide, bis(benzyl mercapto-thiocarbonyl) disulfide, bis(n-butyl mercapto-thiocarbonyl) disulfide, bis(t-butyl mercapto-thiocarbonyl) disulfide, bis(n-heptyl mercapto-thiocarbonyl) disulfide, bis(n- Examples of such disulfides include bis(n-hexylmercapto-thiocarbonyl) disulfide, bis(n-pentylmercapto-thiocarbonyl) disulfide, bis(n-nonylmercapto-thiocarbonyl) disulfide, bis(n-decylmercapto-thiocarbonyl) disulfide, bis(t-dodecylmercapto-thiocarbonyl) disulfide, bis(n-tetradecylmercapto-thiocarbonyl) disulfide, bis(n-hexadecylmercapto-thiocarbonyl) disulfide, and bis(n-octadecylmercapto-thiocarbonyl) disulfide.

Specific examples of dithioester compounds include 2-phenyl-2-propyl benzothioate, 4-cyano-4-(phenylthiocarbonylthio)pentanoic acid, and 2-cyano-2-propyl benzodithioate.

Specific examples of trithiocarbonate compounds include S-(2-cyano-2-propyl)-S-dodecyl trithiocarbonate, 4-cyano-4-[(dodecylsulfanyl-thiocarbonyl)sulfanyl]pentanoic acid, cyanomethyl dodecyl trithiocarbonate, and 2-(dodecylthiocarbonothiolthio)-2-methylpropionic acid.

Specific examples of dithiocarbamate compounds include cyanomethylmethyl(phenyl)carbamodithioate and cyanomethyldiphenylcarbamo-dithioate.

Specific examples of xanthate compounds include xanthogenate esters.

- Aromatic α-methylalkenyl dimer -
An example of the aromatic α-methylalkenyl dimer is 2,4-diphenyl-4-methyl-1-pentene.

Furthermore, as a chain transfer agent, a trithiocarbonate compound such as that used as a RAFT agent in reversible addition-fragmentation chain transfer (RAFT) polymerization, which is a type of living polymerization, can also be preferably used.

The molecular weight of the chain transfer agent is preferably 200 or more, since this can suppress contamination of the apparatus due to sublimation. The upper limit is preferably 1,000 or less, more preferably 800 or less, and even more preferably 600 or less, since this can increase the SH valence per unit mass.

From the viewpoint of adhesion, the content of the chain transfer agent is preferably 0.01% by mass to 10% by mass, more preferably 0.01% by mass to 5% by mass, and even more preferably 0.05% by mass to 1% by mass, based on the total solid content of the curable composition. Only one type of chain transfer agent may be used, or two or more types may be used in combination.

<Other ingredients>
The curable composition according to the present disclosure may contain, as necessary, a sensitizer, a curing accelerator, a filler, a heat curing accelerator, a plasticizer, and other auxiliaries (e.g., conductive particles, defoamers, flame retardants, leveling agents, peeling accelerators, fragrances, surface tension adjusters, etc.). By appropriately incorporating these components, it is possible to adjust properties such as film properties. As these components, the compounds described in paragraph 0182 of WO 2022/085485, the xanthene type epoxy resins described in JP 2021-195421, the xanthene type epoxy resins described in JP 2021-195422 A, and the like can also be used.

The curable composition according to the present disclosure may contain a metal oxide in order to adjust the refractive index of the resulting film. Examples of the metal oxide include TiO ₂ , ZrO ₂ , Al ₂ O ₃ , and SiO ₂ . The primary particle size of the metal oxide is preferably 1 nm to 100 nm, more preferably 3 nm to 70 nm, and even more preferably 5 nm to 50 nm. The metal oxide may have a core-shell structure. In this case, the core may be hollow.

The curable composition according to the present disclosure may contain a light resistance improver. The light resistance improver may be a compound described in paragraph 0183 of WO 2022/085485.

It is also preferable that the curable composition according to the present disclosure is substantially free of terephthalic acid esters. Here, "substantially free" means that the content of terephthalic acid esters in the total amount of the curable composition is 1000 ppb by mass or less, more preferably 100 ppb by mass or less, and particularly preferably zero.

From the viewpoint of environmental regulations, the use of perfluoroalkylsulfonic acid and its salts, and perfluoroalkylcarboxylic acid and its salts may be restricted. When the content of the above-mentioned compounds is reduced in the curable composition according to the present disclosure, the content of perfluoroalkylsulfonic acid (particularly perfluoroalkylsulfonic acid having 6 to 8 carbon atoms in the perfluoroalkyl group) and its salts, and perfluoroalkylcarboxylic acid (particularly perfluoroalkylcarboxylic acid having 6 to 8 carbon atoms in the perfluoroalkyl group) and its salts is preferably in the range of 0.01 ppb to 1,000 ppb, more preferably in the range of 0.05 ppb to 500 ppb, and even more preferably in the range of 0.1 ppb to 300 ppb, based on the total solid content of the curable composition. The curable composition according to the present disclosure may be substantially free of perfluoroalkylsulfonic acid and its salts, and perfluoroalkylcarboxylic acid and its salts. For example, by using a compound that can be a substitute for perfluoroalkylsulfonic acid and its salt, and a compound that can be a substitute for perfluoroalkyl carboxylic acid and its salt, a curable composition that is substantially free of perfluoroalkylsulfonic acid and its salt, and perfluoroalkyl carboxylic acid and its salt may be selected. Examples of compounds that can be a substitute for regulated compounds include compounds that are excluded from regulation due to the difference in the number of carbon atoms in the perfluoroalkyl group. However, the above content does not prevent the use of perfluoroalkylsulfonic acid and its salt, and perfluoroalkyl carboxylic acid and its salt. The curable composition according to the present disclosure may contain perfluoroalkylsulfonic acid and its salt, and perfluoroalkyl carboxylic acid and its salt within the maximum allowable range.

The moisture content of the curable composition according to the present disclosure is preferably 3% by mass or less, more preferably 0.01% by mass to 1.5% by mass, and even more preferably in the range of 0.1% by mass to 1.0% by mass. The moisture content can be measured by the Karl Fischer method.

The curable composition according to the present disclosure can be used by adjusting the viscosity for the purpose of adjusting the film surface state (flatness, etc.), adjusting the film thickness, etc. The value of the viscosity can be appropriately selected as necessary, and is preferably 0.3 mPa·s to 50 mPa·s, and more preferably 0.5 mPa·s to 20 mPa·s at 25° C., for example. The viscosity can be measured, for example, using a cone-plate type viscometer, with the temperature adjusted to 25° C.
In the curable composition according to the present disclosure, the amount of chloride ions in the curable composition is preferably 10,000 ppm or less, more preferably 1000 ppm or less, from the viewpoints of environmental friendliness, suppression of foreign matter generation, suppression of equipment contamination, etc. In order to set the chloride ions in the curable composition within the above range, a raw material with a low chloride ion content may be used, and a method of removing chloride ions by water washing, ion exchange resin, filter filtration, etc. may be used. A known method may be used to measure chloride ions, and examples of the method include ion chromatography and combustion ion chromatography.

<Containment container>
The container for storing the curable composition is not particularly limited, and a known container can be used. In addition, the container described in paragraph 0187 of WO 2022/085485 can also be used as the container.

<Method of preparing curable composition>
The curable composition according to the present disclosure can be prepared by mixing the above-mentioned components. When preparing the curable composition, all components may be simultaneously dissolved and/or dispersed in a solvent to prepare the curable composition, or, if necessary, each component may be appropriately prepared as two or more solutions or dispersions, which are mixed at the time of use (at the time of application) to prepare the curable composition.

In addition, when preparing the curable composition, it is preferable to include a process for dispersing the pigment. In the process for dispersing the pigment, mechanical forces used to disperse the pigment include compression, squeezing, impact, shear, and cavitation. Specific examples of these processes include bead mills, sand mills, roll mills, ball mills, paint shakers, microfluidizers, high-speed impellers, sand grinders, flow jet mixers, high-pressure wet atomization, and ultrasonic dispersion. In addition, when grinding the pigment in a sand mill (bead mill), it is preferable to use beads with a small diameter and increase the bead packing rate, thereby increasing the grinding efficiency. In addition, it is preferable to remove coarse particles by filtration, centrifugation, or the like after the grinding process. In addition, the process and dispersing machine for dispersing the pigment may preferably be the process and dispersing machine described in "Dispersion Technology Encyclopedia, published by Joho Kika Co., Ltd., July 15, 2005" or "Dispersion Technology and Industrial Application Practice Focusing on Suspension (Solid/Liquid Dispersion System) - Comprehensive Data Collection, published by Management Development Center Publishing Department, October 10, 1978", and paragraph number 0022 of JP2015-157893A. In addition, in the process for dispersing the pigment, a salt milling process may be performed to refine the particles. For the materials, equipment, processing conditions, etc. used in the salt milling process, the descriptions in, for example, JP2015-194521A and JP2012-046629A may be referred to. As beads used for dispersion, zirconia, agate, quartz, titania, tungsten carbide, silicon nitride, alumina, stainless steel, glass, or a combination thereof may be used. In addition, an inorganic compound having a Mohs hardness of 2 or more may be used. The composition may contain 1 to 10,000 ppm of the beads.

When preparing the curable composition, it is preferable to filter the curable composition with a filter for the purpose of removing foreign matter and reducing defects. For example, the filters and filtration methods described in paragraphs 0196 to 0199 of WO 2022/085485 can be used.

(Cured product and film)
The cured product according to the present disclosure is a cured product obtained by curing the curable composition according to the present disclosure.
The film according to the present disclosure is a film obtained from the curable composition according to the present disclosure, and is preferably a film obtained by curing the curable composition according to the present disclosure. The film according to the present disclosure can be used for optical filters such as color filters and infrared transmission filters. In particular, it can be preferably used as a color pixel of a color filter. Examples of the color pixel include a red pixel, a green pixel, a blue pixel, a magenta pixel, a cyan pixel, and a yellow pixel, and the like. The color pixel is preferably a green pixel or a blue pixel, and more preferably a green pixel.

The thickness of the film according to the present disclosure can be adjusted as appropriate depending on the purpose, but is preferably 0.1 μm to 20 μm. The upper limit of the film thickness is more preferably 10 μm or less, even more preferably 5 μm or less, particularly preferably 3 μm or less, and most preferably 1.5 μm or less. The lower limit of the film thickness is more preferably 0.2 μm or more, and even more preferably 0.3 μm or more.

(Method for producing a cured product and method for producing a film)
The method for producing a cured product according to the present disclosure and the method for producing a film according to the present disclosure are not particularly limited, but preferably include a step of irradiating the curable composition according to the present disclosure with light having a wavelength of 150 nm to 300 nm.
Examples of light with a wavelength of 150 nm to 300 nm include KrF radiation (wavelength 248 nm) and ArF radiation (wavelength 193 nm).
The light having a wavelength of 150 nm to 300 nm is preferably an excimer laser.
The shape of the resulting cured product is not particularly limited, but is preferably a film.

The film according to the present disclosure can be produced through a process of applying the curable composition according to the present disclosure to a support. The film production method preferably further includes a process of forming a pattern (pixels). Methods for forming the pattern (pixels) include photolithography and dry etching, with photolithography being preferred.

Pattern formation by photolithography preferably includes a step of forming a curable composition layer on a support using the curable composition according to the present disclosure, a step of exposing the curable composition layer in a pattern, and a step of developing and removing the unexposed parts of the curable composition layer to form a pattern (pixels). If necessary, a step of baking the curable composition layer (pre-bake step) and a step of baking the developed pattern (pixels) (post-bake step) may be provided.

In the step of forming the curable composition layer, the curable composition layer is formed on a support using the curable composition according to the present disclosure. The support is not particularly limited and can be appropriately selected depending on the application. For example, a glass substrate, a silicon substrate, etc. can be mentioned, and a silicon substrate is preferable. A charge-coupled device (CCD), a complementary metal oxide semiconductor (CMOS), a transparent conductive film, etc. may be formed on the silicon substrate. A black matrix for isolating each pixel may be formed on the silicon substrate. A base layer may be provided on the silicon substrate to improve adhesion with the upper layer, prevent diffusion of substances, or flatten the substrate surface. The base layer may be formed using a composition obtained by removing the colorant from the curable composition described in this specification, or a composition containing the resin, polymerizable compound, surfactant, etc. described in this specification. The surface contact angle of the base layer is preferably 20° to 70° when measured with diiodomethane. It is also preferable that the surface contact angle is 30° to 80° when measured with water.

　A known method can be used to apply the curable composition. For example, the method described in paragraph 0207 of WO 2022/085485 can be used.

The curable composition layer formed on the support may be dried (prebaked). When a film is produced by a low-temperature process, prebaking may not be performed. When prebaking is performed, the prebaking temperature is preferably 150°C or less, more preferably 120°C or less, and even more preferably 110°C or less. The lower limit can be, for example, 50°C or more, and can also be 80°C or more. The prebaking time is preferably 10 seconds to 300 seconds, more preferably 40 seconds to 250 seconds, and even more preferably 80 seconds to 220 seconds. Prebaking can be performed using a hot plate, an oven, etc.

Next, the curable composition layer is exposed to light in a pattern (exposure step). For example, the curable composition layer can be exposed to light in a pattern by using a stepper exposure machine or a scanner exposure machine through a mask having a predetermined mask pattern. This allows the exposed parts to be cured.

Radiation (light) that can be used for exposure includes g-line and i-line. Light with a wavelength of 300 nm or less (preferably light with a wavelength of 150 nm to 300 nm) can also be used. Examples of light with a wavelength of 300 nm or less include KrF line (wavelength 248 nm) and ArF line (wavelength 193 nm), with KrF line (wavelength 248 nm) being preferred. Long-wavelength light sources of 300 nm or more can also be used.

In addition, during exposure, light may be applied continuously or in pulses (pulse exposure). Pulse exposure is an exposure method in which light is applied and paused repeatedly in short cycles (e.g., milliseconds or less).

The irradiation amount (exposure amount) is, for example, preferably 0.03 J/cm ² to 2.5 J/cm ² , more preferably 0.05 J/cm ² to 1.0 J/cm ^2. The oxygen concentration during exposure can be appropriately selected, and in addition to being performed under air, for example, exposure may be performed under a low-oxygen atmosphere with an oxygen concentration of 19 volume% or less (e.g., 15 volume%, 5 volume%, or substantially oxygen-free), or exposure may be performed under a high-oxygen atmosphere with an oxygen concentration of more than 21 volume% (e.g., 22 volume%, 30 volume%, or 50 volume%). The exposure illuminance can be appropriately set, and can usually be selected from the range of 1000 W/m ² to 100,000 W/m ² (e.g., 5000 W/m ² , 15000 W/m ² , or 35000 W/m ² ). The oxygen concentration and exposure illuminance may be appropriately combined. For example, an oxygen concentration of 10% by volume and an illuminance of 10,000 W/m ² , and an oxygen concentration of 35% by volume and an illuminance of 20,000 W/m ² , can be used.

Next, the unexposed parts of the curable composition layer are developed and removed to form a pattern (pixels). The unexposed parts of the curable composition layer can be developed and removed using a developer. As a result, the unexposed parts of the curable composition layer in the exposure step are dissolved into the developer, and only the photocured parts remain. The temperature of the developer is preferably, for example, 20°C to 30°C. The development time is preferably 20 seconds to 180 seconds. In addition, to improve residue removal, the process of shaking off the developer every 60 seconds and then supplying new developer may be repeated several times.

The developer may be an organic solvent or an alkaline developer, with an alkaline developer being preferred. For example, the developer and development method described in paragraph 0214 of WO 2022/085485 may be used.

After development and drying, it is preferable to perform additional exposure processing or heating processing (post-baking). Additional exposure processing and post-baking are curing processing after development to complete curing. The heating temperature in post-baking is, for example, preferably 100°C to 240°C, more preferably 200°C to 240°C. Post-baking can be performed continuously or batchwise using a heating means such as a hot plate, a convection oven (hot air circulation dryer), or a high-frequency heater to achieve the above conditions for the developed film. When additional exposure processing is performed, it is preferable that the light used for exposure has a wavelength of 400 nm or less. In addition, additional exposure processing may be performed by the method described in Korean Patent Publication No. 10-2017-0122130.

　The method described in paragraph 0216 of WO 2022/085485 can also be used for pattern formation using the dry etching method.

(Optical elements)
The optical element according to the present disclosure has the film according to the present disclosure.
Examples of optical elements include optical filters, lenses, prisms, reflecting mirrors, diffraction gratings, etc. Among these, optical filters are preferred.
The types of optical filters include color filters and infrared transmission filters, and are preferably color filters. The color filter preferably has the film according to the present disclosure as its colored pixels.

The film thickness of the film disclosed herein in the optical filter can be adjusted as appropriate depending on the purpose. The film thickness is preferably 20 μm or less, more preferably 10 μm or less, and even more preferably 5 μm or less. The lower limit of the film thickness is preferably 0.1 μm or more, more preferably 0.2 μm or more, and even more preferably 0.3 μm or more.

The width of the pixels included in the optical filter is preferably 0.4 μm to 10.0 μm. The lower limit is more preferably 0.4 μm or more, even more preferably 0.5 μm or more, and particularly preferably 0.6 μm or more. The upper limit is more preferably 5.0 μm or less, even more preferably 2.0 μm or less, particularly preferably 1.0 μm or less, and most preferably 0.8 μm or less. The Young's modulus of the pixels is preferably 0.5 GPa to 20 GPa, and more preferably 2.5 GPa to 15 GPa.

Each pixel included in the optical filter preferably has high flatness. Specifically, the surface roughness Ra of the pixel is preferably 100 nm or less, more preferably 40 nm or less, and even more preferably 15 nm or less. Although the lower limit is not specified, it is preferably 0.1 nm or more, for example. The surface roughness of the pixel can be measured using, for example, an AFM (atomic force microscope) Dimension 3100 manufactured by Veeco. In addition, the contact angle of water on the pixel can be set to an appropriate preferred value, but is typically in the range of 50° to 110°. The contact angle can be measured using, for example, a contact angle meter CV-DT-A type (manufactured by Kyowa Interface Science Co., Ltd.). In addition, it is preferable that the volume resistance value of the pixel is high. Specifically, the volume resistance value of the pixel is preferably 10 ⁹ Ω·cm or more, more preferably 10 ¹¹ Ω·cm or more. Although the upper limit is not specified, it is preferably 10 ¹⁴ Ω·cm or less, for example. The volume resistance value of the pixel can be measured using an ultra-high resistance meter 5410 (manufactured by Advantest Corporation).

In the optical filter, a protective layer may be provided on the surface of the film according to the present disclosure. By providing a protective layer, various functions such as oxygen blocking, low reflection, hydrophilicity/hydrophobicity, and shielding of light of a specific wavelength (ultraviolet rays, near infrared rays, etc.) can be imparted. The thickness of the protective layer is preferably 0.01 μm to 10 μm, more preferably 0.1 μm to 5 μm. Methods for forming the protective layer include a method of forming the protective layer by applying a composition for forming the protective layer, a chemical vapor deposition method, and a method of attaching a molded resin with an adhesive. The components constituting the protective layer include (meth)acrylic resin, ene-thiol resin, polycarbonate resin, polyether resin, polyarylate resin, polysulfone resin, polyethersulfone resin, polyphenylene resin, polyarylene ether phosphine oxide resin, polyimide resin, polyamideimide resin, polyolefin resin, cyclic olefin resin, polyester resin, styrene resin, polyol resin, polyvinylidene chloride resin, melamine resin, urethane resin, aramid resin, polyamide resin, alkyd resin, epoxy resin, modified silicone resin, fluorine resin, polycarbonate resin, polyacrylonitrile resin, cellulose resin, Si, C, W, Al ₂ O ₃ , Mo, SiO ₂ , Si ₂ N ₄ , etc., and may contain two or more of these components. For example, in the case of a protective layer intended for oxygen blocking, the protective layer preferably contains a polyol resin, SiO ₂ , and Si ₂ N _4. In addition, in the case of a protective layer intended for low reflection, the protective layer preferably contains a (meth)acrylic resin and a fluorine resin.

The protective layer may contain additives such as organic or inorganic particles, absorbents for light of specific wavelengths (e.g., ultraviolet light, near infrared light, etc.), refractive index adjusters, antioxidants, adhesion agents, and surfactants, as necessary. Examples of organic or inorganic particles include polymer particles (e.g., silicone resin particles, polystyrene particles, melamine resin particles), titanium oxide, zinc oxide, zirconium oxide, indium oxide, aluminum oxide, titanium nitride, titanium oxynitride, magnesium fluoride, hollow silica, silica, calcium carbonate, and barium sulfate. Known absorbents can be used as absorbents for light of specific wavelengths. The content of these additives can be adjusted as appropriate, but is preferably 0.1% by mass to 70% by mass, and more preferably 1% by mass to 60% by mass, based on the total mass of the protective layer.

The protective layer may also be the one described in paragraphs 0073 to 0092 of JP2017-151176A.

The optical filter may have a structure in which each pixel is embedded in a space partitioned by partitions, for example in a grid pattern.

(Image sensors and solid-state imaging devices)
An image sensor according to the present disclosure comprises a membrane according to the present disclosure.
Examples of the image sensor include a solid-state imaging element, an X-ray imaging element, an organic thin-film imaging element, etc. Among these, the present invention can be suitably used for a solid-state imaging element.
The solid-state imaging device according to the present disclosure includes the film according to the present disclosure. The configuration of the solid-state imaging device is not particularly limited as long as it functions as a solid-state imaging device, and examples thereof include the following configurations.

The configuration has a plurality of photodiodes constituting a light receiving area of a solid-state imaging element (such as a CCD (charge-coupled device) image sensor or a CMOS (complementary metal-oxide semiconductor) image sensor) on a substrate, a light-shielding film on the photodiodes and the transfer electrodes with only the light receiving parts of the photodiodes open, a device protection film made of silicon nitride or the like formed on the light-shielding film so as to cover the entire light-shielding film and the light receiving parts of the photodiodes, and a color filter on the device protection film.Furthermore, the configuration may have a light-collecting means (e.g., a microlens, etc., the same below) on the device protection film and below the color filter (on the side closer to the substrate), or a configuration may have a light-collecting means on the color filter.
The color filter may have a structure in which each colored pixel is embedded in a space partitioned, for example, in a lattice shape, by partitions. In this case, the partitions preferably have a lower refractive index than each colored pixel. Examples of imaging devices having such a structure include those described in JP 2012-227478 A, JP 2014-179577 A, and WO 2018/043654 A. In addition, as shown in JP 2019-211559 A, an ultraviolet absorbing layer may be provided in the structure of the solid-state imaging element to improve light resistance. An imaging device equipped with a solid-state imaging element according to the present disclosure can be used for digital cameras, electronic devices having an imaging function (such as mobile phones), as well as vehicle-mounted cameras and surveillance cameras.

(Image display device)
The image display device according to the present disclosure includes the film according to the present disclosure. Examples of the image display device include a liquid crystal display device and an organic electroluminescence display device. The definition of the image display device and details of each image display device are described, for example, in "Electronic Display Devices (by Akio Sasaki, published by Kogyo Chosakai Co., Ltd. in 1990)" and "Display Devices (by Junsho Ibuki, published by Sangyo Tosho Co., Ltd. in 1989)". In addition, the liquid crystal display device is described, for example, in "Next Generation Liquid Crystal Display Technology (edited by Tatsuo Uchida, published by Kogyo Chosakai Co., Ltd. in 1994)". There is no particular limitation on the liquid crystal display device to which the present disclosure can be applied, and the present disclosure can be applied to various types of liquid crystal display devices described in the above "Next Generation Liquid Crystal Display Technology".

(Radical Polymerization Initiator Represented by Formula (2))
The radical polymerization initiator according to the present disclosure is a radical polymerization initiator represented by the following formula (2).
The radical polymerization initiator according to the present disclosure is preferably a photoradical polymerization initiator, and more preferably a photoradical polymerization initiator that generates radicals when exposed to light with a wavelength of 150 nm to 300 nm.

In formula (2),
Ar ₁ represents an alkyl group, an aryl group, or a heteroaryl group;
_Ar2 represents a divalent organic group;
_X11 and _X12 each independently represent a single bond, O, S, _NR , _CRxRy , or C=O; R, _Rx , and _Ry each independently represent a hydrogen atom, an alkyl group, or an aryl group;
R ₁₁ and R ₁₂ each independently represent an alkyl group, an aryl group, a halogen atom, a nitro group, a hydroxyl group, an alkoxy group, an aryloxy group, an alkylthio group, or an arylthio group;
R ₁₅ to R ₁₉ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a nitro group, an alkoxy group, or an aryloxy group, two or more of R ¹⁵ to R ¹⁹ may be bonded to each other to form a ring structure, and the ring structure thus formed may be an aromatic ring;
Y ₁ represents a hydrogen atom, an alkyl group or an aryl group;
R ₁ represents an alkyl group, an aryl group, a heteroaryl group, an alkoxy group, an aryloxy group, or a heteroaryloxy group;
m and n each independently represent 0 or 1;
p and q each independently represent an integer of 0 to 3.

The preferred embodiments of each symbol in formula (2) have been described in the curable composition, so they will not be described here.

The present disclosure will be described in more detail below with reference to examples. The materials, amounts used, ratios, processing contents, processing procedures, etc. shown in the following examples can be changed as appropriate without departing from the spirit of the present disclosure. Therefore, the scope of the present disclosure is not limited to the specific examples shown below. In the present examples, "%" and "parts" mean "% by mass" and "parts by mass", respectively, unless otherwise specified.
The radical polymerization initiators A-1 to A-199 used in the examples are the same compounds as the radical polymerization initiators A-1 to A-199 described above as specific examples of the radical polymerization initiator represented by formula (1).

Synthesis Example 1: Synthesis of Radical Polymerization Initiator A-1

<<Synthesis of Intermediate A-1a>>
16.7 g of N-ethylcarbazole and 100 mL of chlorobenzene were added to a three-neck flask and cooled to 0°C. 13.9 g of aluminum chloride was added thereto and 15.8 g of p-fluorobenzoyl chloride was added dropwise. The mixture was stirred at room temperature (25°C, the same applies below) for 2 hours and added to ice water. The precipitated solid was filtered and washed with methanol to obtain 26.2 g of intermediate A-1a.

<<Synthesis of Intermediate A-1b>>
15.4 g of intermediate A-1a and 24.1 g of 3-acetyl-1H-indole were added to a three-neck flask and dissolved in 200 mL of dimethylformamide. 16.6 g of potassium carbonate was added and heated and stirred at 150° C. for 6 hours. The resulting reaction solution was added to water, and the resulting solid was filtered. This was recrystallized from isopropyl alcohol to obtain 29.5 g of intermediate A-1b.

<<Synthesis of Radical Polymerization Initiator A-1>>
18.1 g of intermediate A-1b was added to a three-neck flask and dissolved in 150 mL of tetrahydrofuran. 7.9 g of hydroxylamine hydrochloride, 8.8 g of sodium acetate, and 50 mL of pure water were added to this and heated and stirred at 60°C for 6 hours. The resulting reaction solution was separated into ethyl acetate and water, and the organic layer was dried over sodium sulfate and then concentrated. Next, this concentrate was dissolved in tetrahydrofuran and cooled to 0°C in a nitrogen atmosphere in a three-neck flask. 5.9 g of pyridine was added, and 4.2 g of acetyl chloride was dropped. The reaction solution was stirred at room temperature for 2 hours, extracted with ethyl acetate, and washed with water. The organic layer was dried over sodium sulfate and then concentrated. The resulting solid was reslurried and purified with methanol, and then filtered to obtain 10.1 g of radical polymerization initiator A-1.

The radical polymerization initiator A-1 was confirmed to be the radical polymerization initiator A-1 by NMR spectrum. Radical polymerization initiator A-1 was analyzed by ¹ H NMR. The results are shown below.
^1H NMR (deuterated chloroform, 400MHz, internal standard: tetramethylsilane) δ = 1.37 (t, 3H), 2.21 (s, 3H), 3.21 (s, 3H), 4.53 (q, 2H), 7.1-8.0 (m, 13H), 8.38 (d, 2H), 8.74 (s, 1H), 8.95 (d, 1H)

<<Synthesis of Intermediate A-30a>>
16.7 g of N-ethylcarbazole and 100 mL of chlorobenzene were added to a three-neck flask and cooled to 0°C. 13.9 g of aluminum chloride and 15.4 g of o-toluoyl chloride were added to the mixture. The mixture was stirred at room temperature (25°C, the same below) for 2 hours and cooled again to 0°C. 14.5 g of aluminum chloride were added to the mixture and 19.5 g of 4-fluoro-2-methylbenzoyl chloride were added dropwise. The mixture was stirred at room temperature (25°C, the same below) for 2 hours and added to ice water. The precipitated solid was collected by filtration and washed with methanol, obtaining 26.2 g of intermediate A-30a.

<<Synthesis of Intermediate A-30b>>
22.4 g of intermediate A-30a and 29.1 g of 3-(3-cyclopentylpropyl-1-yl)-1H-indole were added to a three-neck flask and dissolved in 300 mL of dimethylformamide. 16.6 g of potassium carbonate was added and heated and stirred at 150° C. for 6 hours. The resulting reaction solution was added to water, and the resulting solid was filtered. This was recrystallized from isopropyl alcohol to obtain 58.2 g of intermediate A-30b.

In the same manner as in the synthesis of radical polymerization initiator A-1, an oxime reaction of intermediate A-30b was carried out to obtain radical polymerization initiator A-30.

It was confirmed from the NMR spectrum that the radical polymerization initiator A-30 was the radical polymerization initiator A-1. The radical polymerization initiator A-1 was analyzed by ¹ H NMR. The results are shown below.
^1H NMR (deuterated chloroform, 400MHz, internal standard: tetramethylsilane) δ = 0.8-1.0 (m, 2H), 1.37 (t, 3H), 1.5-2.0 (m, 11H), 2.21 (s, 3H), 2.24 (s, 3H), 2.41 (s, 3H), 2.45 (t, 2H), 3.21 (s, 3H), 4.53 (q, 2H), 7.1-8.0 (m, 14H), 8.38 (d, 2H), 8.74 (s, 1H), 8.95 (d, 1H)

Radical polymerization initiator A-78 was synthesized in the same manner as radical polymerization initiator A-30, except that N-ethylcarbazole was replaced with dibenzothiophene and 3-(3-cyclopentylpropyl-1-yl)-1H-indole was replaced with 3-(2-cyclopentylethyl-1-yl)-1H-indole.

It was confirmed from the NMR spectrum that it was radical polymerization initiator A-78. Radical polymerization initiator A-1 was analyzed by ¹ H NMR. The results are shown below.
^1H NMR (deuterated chloroform, 400MHz, internal standard: tetramethylsilane) δ = 1.2 (m, 2H), 1.5-2.0 (m, 7H), 2.35 (s, 3H), 2.36 (s, 3H), 2.49 (s, 3H), 2.90 (t, 2H), 7.2-8.0 (m, 13H), 8.49 (m, 1H), 8.67 (s, 1H), 8.70 (s, 1H)

Radical polymerization initiator A-92 was synthesized in the same manner as radical polymerization initiator A-30, except that N-ethylcarbazole was replaced with dibenzofuran and 3-(3-cyclopentylpropyl-1-yl)-1H-indole was replaced with 3-(2-cyclopentylethyl-1-yl)-1H-indole.

It was confirmed from the NMR spectrum that it was radical polymerization initiator A-92. Radical polymerization initiator A-1 was analyzed by ¹ H NMR. The results are shown below.
^1H NMR (deuterated chloroform, 400MHz, internal standard: tetramethylsilane) δ = 1.2 (m, 2H), 1.5-2.0 (m, 7H), 2.35 (s, 3H), 2.36 (s, 3H), 2.49 (s, 3H), 2.90 (t, 2H), 7.2-7.8 (m, 13H), 8.02 (dd, 1H), 8.11 (dd, 1H), 8.47 (s, 2H)

<<Synthesis of Intermediate A-172b>>
Intermediate A-172b was synthesized in the same manner as in the synthesis of intermediate A-30B, except that 3-(3-cyclopentylpropyl-1-yl)-1H-indole was changed to 3-(octan-1-yl)-1H-indole.

6.7 g of intermediate A-172b was added to a three-neck flask and dissolved in 100 mL of tetrahydrofuran. 1.6 g of sodium methoxide was added to this and cooled to 0°C. 3.5 g of isoamyl nitrite was added dropwise to this and stirred at room temperature for another 2 hours. The resulting reaction solution was separated into ethyl acetate and water, and the organic layer was dried over sodium sulfate and then concentrated. Next, this concentrate was dissolved in 150 mL of tetrahydrofuran and cooled to 0°C in a nitrogen atmosphere in a three-neck flask. 2.4 g of pyridine was added, and 2.9 g of acetyl chloride was added dropwise. The reaction solution was stirred at room temperature for 2 hours, extracted with ethyl acetate and washed with water. The organic layer was dried over sodium sulfate and then concentrated. The resulting solid was reslurried and purified in methanol and then filtered to obtain 3.9 g of radical polymerization initiator A-172.

It was confirmed from the NMR spectrum that it was radical polymerization initiator A-78. Radical polymerization initiator A-1 was analyzed by ¹ H NMR. The results are shown below.
^1H NMR (deuterated chloroform, 400MHz, internal standard: tetramethylsilane) δ = 0.88 (t, 3H), 1.35 (t, 3H), 1.3-1.5 (m, 8H), 2.21 (s, 3H), 2.24 (s, 3H), 2.41 (s, 3H), 2.47 (t, 2H), 4.51 (q, 2H), 7.1-8.0 (m, 14H), 8.35 (d, 1H), 8.49 (s, 1H), 8.72 (s, 1H), 8.91 (d, 1H)

The radical polymerization initiator A-196 was synthesized in the same manner as in the synthesis of radical polymerization initiator A-30, except that N-ethylcarbazole was replaced with 9,9-diethyl-2-nitro-9H-fluorene and 3-(3-cyclopentylpropyl-1-yl)-1H-indole was replaced with 3-(2-cyclopentylethyl-1-yl)-1H-indole.

It was confirmed from the NMR spectrum that it was radical polymerization initiator A-196. Radical polymerization initiator A-1 was analyzed by ¹ H NMR. The results are shown below.
^1H NMR (deuterated chloroform, 400MHz, internal standard: tetramethylsilane) δ = 0.89 (t, 6H), 1.2 (m, 2H), 1.43 (q, 4H), 1.5-2.0 (m, 7H), 2.31 (s, 3H), 2.33 (s, 3H), 2.48 (s, 3H), 2.64 (t, 2H), 7.2-7.8 (m, 9H), 8.12 (dd, 1H), 8.24 (dd, 1H), 8.98 (s, 2H)

<Synthesis Example 7: Synthesis method of radical polymerization initiator other than those described above>
Radical polymerization initiators A-1 to A-91, A-93 to A-195, and A-197 to A-199 were obtained in a similar manner to Synthesis Example 1 except that the raw materials and the like were changed.

<Preparation of Dispersion>
A mixture of the raw materials shown in Table 6 below was mixed and dispersed for 3 hours using a bead mill (zirconia beads 0.1 mm diameter). Next, a dispersion process was carried out using a high-pressure disperser NANO-3000-10 with a pressure reducing mechanism (manufactured by Japan BEE Co., Ltd.) under conditions of a pressure of 2,000 kg/ ^cm2 and a flow rate of 500 g/min. This dispersion process was repeated a total of 10 times to obtain a dispersion. The numerical values showing the blend amounts shown in Table 6 below are parts by mass. The numerical values of the blend amounts of dispersants are numerical values converted into solid content.

Details of the materials indicated by the abbreviations in Table 6, which shows the formulation of the above dispersion, are as follows:

<Coloring Agent>
PR264: C.I. Pigment Red 264 [diketopyrrolopyrrole compound, red pigment (R pigment)]
PR254: C.I. Pigment Red 254 [diketopyrrolopyrrole compound, red pigment (R pigment)]
PR291: C.I. Pigment Red 291 [brominated diketopyrrolopyrrole compound, red pigment (R pigment)]
PR272: C.I. Pigment Red 272 [diketopyrrolopyrrole compound, red pigment (R pigment)]
PG36: C.I. Pigment Green 36 [copper phthalocyanine complex, green pigment (G pigment)]
PG58: C.I. Pigment Green 58 [zinc phthalocyanine complex, green pigment (G pigment)]
PY129: C.I. Pigment Yellow 129 [azomethine copper complex, yellow pigment (Y pigment)]
PY139: C.I. Pigment Yellow 139 [isoindoline compound, yellow pigment (Y pigment)]
PY185: C.I. Pigment Yellow 185 [isoindoline compound, yellow pigment (Y pigment)]
PV23: C.I. Pigment Violet 23 [dioxazine compound, purple pigment (V pigment)]
PB16: C.I. Pigment Blue 16 [metal-free phthalocyanine compound, blue pigment (B pigment)]
PB15:6: C.I. Pigment Blue 15:6 [copper phthalocyanine complex, blue pigment (B pigment)]
IR dye: a compound having the following structure (near infrared absorbing pigment, in the following structural formula, Me represents a methyl group and Ph represents a phenyl group).

TiBk: Titanium black [black pigment (Bk pigment)]
Zr oxynitride: Zirconium oxynitride [black pigment (Bk pigment)]

<Pigment Derivatives>
S-1: The following compound S-2: The following compound S-3: The following compound S-4: The following compound

<Dispersant>
P-1: 30% by mass propylene glycol monomethyl ether acrylate (PGMEA) solution of a resin having the following structure. The number attached to the main chain is the molar ratio, and the number attached to the side chain is the number of repeating units. Mw: 20,000.

P-2: 30% by weight PGMEA solution of the resin with the following structure. The number attached to the main chain is the molar ratio, and the number attached to the side chain is the number of repeating units. Mw: 28,000. In the formula, r = 15, s = 63, t = 5, u = 17, n = 9.

P-3: 30% by weight PGMEA solution of the resin with the following structure. The number attached to the main chain is the molar ratio, and the number attached to the side chain is the number of repeating units. Mw: 21,000.

P-4: 30% by weight PGMEA solution of the resin with the following structure. The numbers added to the side chains are the number of repeating units. Mw: 11,400.

P-5: 30% by weight PGMEA solution of the resin with the following structure. The numbers added to the side chains are the number of repeating units. Mw: 10,000.

<Solvent>
S-1: Propylene glycol monomethyl ether acetate (PGMEA)
S-2: Propylene glycol monomethyl ether (PGME)
S-3: Cyclohexanone

<Preparation of Curable Composition>
Dispersions described in Tables 7 to 12 below, resins described in Tables 7 to 12 below, radical curable compounds described in Tables 7 to 12 below, radical polymerization initiators described in Tables 7 to 12 below, chain transfer agents described in Tables 7 to 12 below, solvents described in Tables 7 to 12 below, 1 part by mass of an epoxy compound (EHPE-3150, manufactured by Daicel Corporation), 1 part by mass of an ultraviolet absorber (TINUVIN326, manufactured by BASF Corporation), 1 part by mass of the surfactant 1 shown below, and 0.1 part by mass of a polymerization inhibitor (p-methoxyphenol) were mixed to prepare curable compositions of each of the examples and comparative examples.

Thiol chain transfer agent F-1: The following compound

Thiol chain transfer agent F-2: The following compound

Chain transfer agent F-3: The following compound, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.

Surfactant 1: 1% by mass solution of KF-6001 (polydimethylsiloxane modified with carbinol at both ends, manufactured by Shin-Etsu Chemical Co., Ltd.) in PGMEA.

　Details of the materials indicated by the abbreviations in Tables 7 to 12, which show the formulations of the curable compositions, other than those mentioned above, are as follows:

<Resin>
Ba-1: Resin having the following structure (the numbers attached to the main chain are molar ratios. Weight average molecular weight: 11,000)

Ba-2: Resin with the following structure (numbers attached to the main chain are molar ratios. Weight average molecular weight 15,000)

Ba-3: Resin with the following structure (the numbers attached to the main chain are molar ratios. The sum of x, y, and z is 50. Mw = 15,000)

<Radically curable compound>
D-1: KAYARAD DPHA (a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate, manufactured by Nippon Kayaku Co., Ltd.)
D-2: NK Ester A-DPH-12E (ethylene oxide (EO) modified hexafunctional acrylate compound, manufactured by Shin-Nakamura Chemical Co., Ltd.)
D-3: NK Ester A-TMMT (pentaerythritol tetraacrylate, manufactured by Shin-Nakamura Chemical Co., Ltd.)
D-4: Aronix M-510 (a tri- to tetra-functional acrylate compound, manufactured by Toagosei Co., Ltd.)
D-5: Light Acrylate DCP-A (bifunctional alicyclic acrylate compound, manufactured by Kyoeisha Chemical Co., Ltd.)

<Radical polymerization initiator used in combination>
a-1: Compound having the following structure

a-2: Compound with the following structure

a-3: Compound with the following structure

a-4: Compound with the following structure

a-5: Compound with the following structure

a-6: Compound with the following structure

a-7: Compound with the following structure

<Radical Polymerization Initiator for Comparison>
CA-1: The following compound

<Radical Polymerization Initiator for Comparison>
CA-2: The following compound

＜Evaluation＞

<<Sensitivity>>
Each curable composition was applied onto an 8-inch (203.2 mm) silicon wafer with an undercoat layer using a spin coater, and then heated (prebaked) at 100° C. for 120 seconds using a hot plate to obtain a coating film with a thickness of 0.4 μm.
Next, the coating film was exposed to light (KrF radiation) having a wavelength of 248 nm through a patterned mask (0.5 μm×0.5 μm) using a KrF scanner exposure machine under conditions of an illuminance of 35,000 W/m ² and an exposure dose of 20 mJ/cm ² (exposure step).
Next, the exposed coating film was subjected to shower development using a 0.3 mass % aqueous solution of tetramethylammonium hydroxide (TMAH) as a developer at 23° C. for 60 seconds, followed by rinsing with pure water by spin shower and post-baking at 230° C. for 2 minutes to form a pattern.
The exposure dose was changed in increments of 10 mJ/ ^cm2 up to 200 mJ/ ^cm2 , and the exposure dose capable of forming a pattern with a line width of 0.7 μm was examined, and the sensitivity was evaluated based on the following evaluation criteria. The results are shown in Tables 13 to 17.
-Evaluation criteria-
A: The exposure amount was 60 mJ/ ^cm2 or less.
B: The exposure amount was more than 60 mJ/ ^cm2 and 100 mJ/ ^cm2 or less.
C: The exposure amount was more than 100 mJ/ ^cm2 and 150 mJ/ ^cm2 or less.
D: The exposure amount was more than 150 mJ/ ^cm2 and 200 mJ/ ^cm2 or less.
E: 200 mJ/ ^cm2 or more.

<<Adhesion and Residue Suppression>>
A pattern was formed in the same manner as in the sensitivity evaluation, except that the exposure dose was set to 100 mJ/cm ² .
The obtained patterns were observed at a magnification of 20,000 times using a scanning electron microscope (S-4800H, Hitachi High-Technologies Corporation). The number of peeled patterns out of the total number of patterns (1071 pieces x 1071 pieces) formed in a partial area of the observed image was counted, and the adhesion was evaluated based on the following evaluation criteria. The results are shown in Tables 13 to 17.
-Evaluation criteria-
A: The number of peeled patterns was 10 or less.
B: The number of peeled patterns was more than 10 and 20 or less.
C: The number of peeled patterns was more than 20 and 50 or less.
D: The number of peeled patterns was more than 50 and 200 or less.
E: The number of peeled patterns was more than 200.

The images obtained by the scanning electron microscope were evaluated for residue suppression properties according to the following evaluation criteria. The results are shown in Tables 13 to 17.
-Evaluation criteria-
A: The linearity of the pattern was excellent, and there was very little residue between the patterns.
B: The linearity of the pattern was excellent, and there was little residue between the patterns.
C: The linearity of the pattern was slightly poor, but there was little residue between the patterns.
D: The linearity of the pattern was poor, and there was a large amount of residue between the patterns.
E: There was too much residue, so no pattern was formed and the gap between the patterns could not be confirmed.

<<Inhibition of film thickness change>>
A pattern was formed in the same manner as in the sensitivity evaluation, except that the exposure dose was set to 100 mJ/cm ² .
The thickness of the coating film after pre-baking and after post-baking was measured, and the film thickness change suppression ability was evaluated based on the following evaluation criteria. The results are shown in Tables 13 to 17.
A: The rate of change in the coating film calculated by the formula (thickness of the coating film after pre-baking-thickness of the coating film after post-baking)/thickness of the coating film after pre-baking×100 was 1% or less.
B: The coating film change rate was more than 1% and 5% or less.
C: The coating film change rate was more than 5% and 10% or less.
D: The coating film change rate was more than 10% and 20% or less.
E: The coating film change rate was more than 20%.

As shown in Tables 13 to 17 above, the curable compositions of the Examples were superior in sensitivity generated from the obtained cured products and adhesion to substrates to the curable compositions of the Comparative Examples.
Furthermore, as shown in Tables 13 to 17 above, the curable compositions of the examples are also excellent in suppressing the generation of residues and suppressing changes in film thickness.

The curable compositions of the examples can be irradiated with KrF rays instead of i rays to obtain the same effect. The conditions for KrF ray irradiation can be, for example, exposure light: KrF rays (wavelength 248 nm), exposure dose: 10 mJ/cm ² to 500 mJ/cm ² , maximum instantaneous illuminance: 250,000,000 W/m ² (average illuminance: 30,000 W/m ² ), pulse width: 30 nanoseconds, and frequency: 4 kHz.

In addition, the coating (cured) thickness in each of Examples 1 to 200 was changed to 0.2 μm and 2.0 μm, but the evaluation was performed in the same manner. The same evaluation results as those described above were obtained.

(Example 301: Fabrication of solid-state imaging device)
The curable composition of Example 1 was applied on a silicon wafer by spin coating so that the film thickness after film formation was 0.4 μm. Then, using a hot plate, it was heated at 100 ° C. for 2 minutes. Then, using an i-line stepper exposure device FPA-3000i5 + (manufactured by Canon Inc.), it was exposed through a mask of a 1.0 μm square dot pattern at 1,000 mJ / cm ^2. Then, using a 0.3 mass % aqueous solution of tetramethylammonium hydroxide (TMAH), paddle development was performed at 23 ° C. for 60 seconds. Thereafter, it was rinsed with a spin shower and further washed with pure water. Then, using a hot plate, it was heated at 200 ° C. for 5 minutes to form a red pattern on the silicon wafer by curing the curable composition of Example 1. Similarly, the curable composition of Example 6 (green) and the curable composition of Example 11 (blue) were patterned in sequence to form a red, green and blue colored pattern (Bayer pattern).
The Bayer pattern is a repeated 2×2 array of color filter elements having one red element, two green elements, and one blue element, as disclosed in U.S. Pat. No. 3,971,065.
The obtained color filter was incorporated into a solid-state imaging device according to a known method. It was confirmed that the solid-state imaging device had excellent adhesion in the cured film and favorable image recognition ability, regardless of which curable composition prepared in the Examples was used.

The disclosures of Japanese Patent Application No. 2022-185873 filed on November 21, 2022 and Japanese Patent Application No. 2023-063052 filed on April 7, 2023 are incorporated herein by reference in their entirety.
All publications, patent applications, and technical standards mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent application, or technical standard was specifically and individually indicated to be incorporated by reference.

Claims

a radical polymerization initiator having a group having an indole skeleton, a group having three or more condensed rings different from the indole skeleton, and a (keto)oxime ester group;
A radical curable compound;
Including,
the group having three or more condensed rings and the (keto)oxime ester group are bonded to the group having an indole skeleton.
The curable composition according to claim 1 , wherein the radical polymerization initiator is a compound represented by the following formula (1):

In formula (1),
Z1 represents any one of an alkyl group, an aryl group, a heteroaryl group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, a hydroxyl group, a carboxyl group, a cyano group, a nitro group, a halogen atom, and an acyl group;
X represents a group having three or more condensed rings;
L represents a single bond or a divalent organic group;
R 15 to R 19 each independently represent a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a nitro group, an alkoxy group, or an aryloxy group, two or more of R 15 to R 19 may be bonded to each other to form a ring structure, and the ring structure thus formed may be an aromatic ring;
Y 1 represents a hydrogen atom, an alkyl group or an aryl group;
R 1 represents an alkyl group, an aryl group, a heteroaryl group, an alkoxy group, an aryloxy group, or a heteroaryloxy group;
m and n each independently represent 0 or 1.
The curable composition according to claim 1 , wherein the radical polymerization initiator is a compound represented by the following formula (2):

In formula (2),
Ar 1 represents an alkyl group, an aryl group, or a heteroaryl group;
Ar2 represents a divalent organic group;
X11 and X12 each independently represent a single bond, O, S, NR, CRxRy , or C=O;
R, Rx , and Ry each independently represent a hydrogen atom, an alkyl group, or an aryl group;
R 11 and R 12 each independently represent an alkyl group, an aryl group, a halogen atom, a nitro group, a hydroxyl group, an alkoxy group, an aryloxy group, an alkylthio group, or an arylthio group;
R 15 to R 19 each independently represent a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a nitro group, an alkoxy group, or an aryloxy group, two or more of R 15 to R 19 may be bonded to each other to form a ring structure, and the ring structure thus formed may be an aromatic ring;
Y 1 represents a hydrogen atom, an alkyl group or an aryl group;
R 1 represents an alkyl group, an aryl group, a heteroaryl group, an alkoxy group, an aryloxy group, or a heteroaryloxy group;
m and n each independently represent 0 or 1;
p and q each independently represent an integer of 0 to 3.
The curable composition according to claim 2 or 3, wherein Y 1 is a group represented by the following formula (3):

In formula (3),
R2 represents an alkyl group, provided that when L2 is CHR, R2 may be a hydrogen atom;
R3 represents a hydrogen atom or an alkyl group;
R4 represents an alkyl group;
L1 and L2 each independently represent CHR, O, S, or NR, and each R independently represents a hydrogen atom or an alkyl group;
Two or more of R 2 , R 3 , R 4 and R may be bonded to each other to form a ring structure;
Z2 represents a single bond or an alkylene group having 1 to 6 carbon atoms;
* indicates the linkage to the oxime group.
The curable composition according to claim 2 or 3, wherein Y 1 is a group represented by the following formula (4):

In formula (4),
L3 and L4 each independently represent CHR, O, S, or NR, and at least one of L3 and L4 is CHR, in which R represents a hydrogen atom or an alkyl group;
Each R5 independently represents a hydrogen atom or an alkyl group;
r represents an integer from 1 to 6;
* indicates the linkage to the oxime group.
The curable composition of claim 3 , wherein Ar 1 is an aryl or heteroaryl group.
The curable composition of claim 3 , wherein Ar 2 is an arylene group.
The curable composition according to claim 2 or 3, wherein m is 1.
The curable composition according to claim 1 or claim 2, further comprising a colorant.
The curable composition according to claim 1 or 2, further comprising a thiol-based chain transfer agent.
The curable composition according to claim 1 or 2 is irradiated with an excimer laser beam having a wavelength of 150 nm to 300 nm.
A method for producing a cured product.
A film obtained by curing the curable composition according to claim 1 or 2.
An optical element comprising the film according to claim 12.
An image sensor including the film according to claim 12.
A solid-state imaging device including the film according to claim 12.
An image display device including the film according to claim 12.
A radical polymerization initiator represented by the following formula (2):

In formula (2),
Ar 1 represents an alkyl group, an aryl group, or a heteroaryl group;
Ar2 represents a divalent organic group;
X11 and X12 each independently represent a single bond, O, S, NR , CRxRy , or C=O; R, Rx , and Ry each independently represent a hydrogen atom, an alkyl group, or an aryl group;
R 11 and R 12 each independently represent an alkyl group, an aryl group, a halogen atom, a nitro group, a hydroxyl group, an alkoxy group, an aryloxy group, an alkylthio group, or an arylthio group;
R 15 to R 19 each independently represent a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a nitro group, an alkoxy group, or an aryloxy group, two or more of R 15 to R 19 may be bonded to each other to form a ring structure, and the ring structure thus formed may be an aromatic ring;
Y 1 represents a hydrogen atom, an alkyl group or an aryl group;
R 1 represents an alkyl group, an aryl group, a heteroaryl group, an alkoxy group, an aryloxy group, or a heteroaryloxy group;
m and n each independently represent 0 or 1;
p and q each independently represent an integer of 0 to 3.