JP2024156489A - Optical Materials - Google Patents

Abstract

The present invention provides an optical material that is a novel high refractive index polymer material that has excellent moldability and can be used to manufacture optical components by molding without going through a dissolution process.
The formula:
CH ₂ =C(-X ¹ )-C(=O)-Y ¹ -(L ¹ O) _p -TIP
[Wherein,
TIP is a triiodophenyl group;
^X1 is a hydrogen atom, a methyl group or a halogen atom;
^Y1 is -O- or -NH-;
Each ^L1 is independently an alkylene group having 1 to 10 carbon atoms;
p is 1 or more and 5 or less.
An optical material comprising an iodine-containing polymer including a repeating unit derived from a triiodophenyl group-containing acrylic monomer (1) represented by the following formula:
[Selection diagram] None

Description

The present disclosure particularly relates to optical materials containing iodine-containing polymers for use in high refractive index polymer materials.

In recent years, research and development of high refractive index polymer materials has progressed. Patent Document 1 discloses an iodine-containing polymer containing repeating units derived from a triiodophenyl group-containing acrylic monomer as a high refractive index polymer material.

JP 2022-131503 A

Conventionally, optical components are formed by dissolving a highly refractive polymer material in an appropriate solvent and casting it onto a substrate. However, this manufacturing method requires the selection of a solvent, management of the solvent, dissolving, applying, and removing the solvent, which can lead to poor productivity and be industrially disadvantageous.

The objective of this disclosure is to provide an optical material that is a novel high refractive index polymer material that has excellent moldability and can be molded to produce optical components without going through a dissolution process.

One embodiment of the present disclosure is as follows:
[Item 1]
formula:
CH ₂ =C(-X ¹ )-C(=O)-Y ¹ -(L ¹ O) _p -TIP
[Wherein,
TIP is a triiodophenyl group;
^X1 is a hydrogen atom, a methyl group or a halogen atom;
^Y1 is -O- or -NH-;
Each ^L1 is independently an alkylene group having 1 to 10 carbon atoms;
p is 1 or more and 5 or less.
An optical material comprising an iodine-containing polymer including a repeating unit derived from a triiodophenyl group-containing acrylic monomer (1) represented by the following formula:
[Item 2]
Each ^L1 is independently an alkylene group having 1 to 4 carbon atoms;
Item 2. The optical material according to item 1, wherein p is 1 to 3.
[Item 3]
-Y ¹ -(L ¹ O) _p - is a group represented by the formula:
-O-CH ₂ CH ₂ -O-
Item 3. The optical material according to item 1 or 2, represented by the formula:
[Item 4]
Item 4. The optical material according to any one of items 1 to 3, which is for molding.
[Item 5]
Item 5. The optical material according to any one of items 1 to 4, which is for forming a free-standing film.
[Item 6]
The iodine-containing polymer has the following formula:
CH ₂ =C(-X ² )-C(=O)-Y ² -R
[In the formula, TIP is the triiodophenyl group,
^X2 is a hydrogen atom, a methyl group or a halogen atom;
^Y2 is -O- or -NH-;
R is an organic group having 2 to 30 carbon atoms.
Item 6. The optical material according to any one of items 1 to 5, having a repeating unit derived from a triiodophenyl group-free acrylic monomer (2) represented by the following formula:
[Item 7]
Item 7. The optical material according to item 6, wherein R is an alkylene group or a (poly)oxyalkylene group.
[Item 8]
Item 8. The optical material according to any one of items 1 to 7, wherein the content of the repeating unit derived from the monomer (1) in the iodine-containing polymer is 75% by weight or more.
[Item 9]
Item 9. The optical material according to any one of items 1 to 8, wherein the iodine-containing polymer has a structure derived from a molecular weight control agent.
[Item 10]
Item 10. An optical component comprising the optical material according to any one of items 1 to 9.
[Item 11]
Item 11. The optical component according to item 10, which is a molded product of the optical material.
[Item 12]
Item 12. The optical component according to item 10 or 11, which is a free-standing film.
[Item 13]
Item 10. A method for producing an optical component, comprising a step of molding the optical material according to any one of items 1 to 9.
[Item 14]
Item 14. A method for producing an optical component according to item 13, comprising the steps of: forming a film of an optical material on a substrate by performing the molding process; and separating the film from the substrate.
[Item 15]
Item 13. An optical article comprising the optical component according to any one of items 10 to 12.

The optical material disclosed herein has excellent moldability and exhibits a high refractive index.

<Optical materials>
The optical material in the present disclosure is a material that is a raw material for various optical components, and is particularly used in optical components that utilize its high refractive index. The optical material in the present disclosure contains an iodine-containing polymer described below.

[Iodine-containing polymer]
The iodine-containing polymer in the present disclosure contains a repeating unit derived from a triiodophenyl group-containing acrylic monomer (1).

[Characteristics of iodine-containing polymers]
The iodine-containing polymer of the present disclosure has excellent moldability. The term "excellent moldability" means, for example, that the polymer exhibits plasticity and viscosity suitable for molding and can be formed into a predetermined shape. The molding process may be a thermoforming process, or the polymer may be molded in a softened state by heating. Examples of the molding process include compression molding, extrusion molding, and injection molding. Conventional iodine-containing polymers have problems such as not exhibiting sufficient moldability and softening properties, and are not suitable for molding.

In addition, the iodine-containing polymer of the present disclosure can be handled as a free-standing film after molding. A free-standing film is one that does not have a base material or substrate and can maintain its shape by itself. Conventional iodine-containing polymers do not have sufficient moldability, and even if they are made into a film, the flexibility and mechanical strength of the polymer are poor, so that it is difficult to separate from the base material by being crushed, etc., and it is not possible to form a free-standing film.

Furthermore, the optical material disclosed herein may be excellent not only in refractive index and moldability, but also in solubility, film-forming properties, and/or heat resistance, etc.

(Refractive index of iodine-containing polymer)
The refractive index of the iodine-containing polymer in the present disclosure may be 1.65 or more, 1.70 or more, 1.72 or more, 1.76 or more, 1.78 or more, 1.80 or more, or 1.82 or more, preferably 1.72 or more, and more preferably 1.78 or more.

(Heat resistance of iodine-containing polymer)
The heat resistance temperature of the iodine-containing polymer in the present disclosure (the temperature at which a 5% weight loss is observed when the temperature is increased at a heating rate of 10° C./min in a nitrogen gas atmosphere) may be 250° C. or higher, 260° C. or higher, 270° C. or higher, 280° C. or higher, 290° C. or higher, 300° C. or higher, 310° C. or higher, or 320° C. or higher, preferably 260° C. or higher, and more preferably 280° C. or higher.

(Molecular Weight of Iodine-Containing Polymer)
The weight average molecular weight of the iodine-containing polymer in the present disclosure may be 10,000 or more, 25,000 or more, 50,000 or more, 75,000 or more, 100,000 or more, 150,000 or more, 200,000 or more, 250,000 or more, or 300,000 or more, preferably 50,000 or more, more preferably 75,000 or more. The number average molecular weight of the iodine-containing polymer in the present disclosure may be 3,000,000 or less, 2,000,000 or less, 1,000,000 or less, 500,000 or less, 250,000 or less, 150,000 or less, or 100,000. The molecular weight in the above range, particularly the above lower limit or more, is suitable for the molding processability and refractive index of the iodine-containing polymer. The weight average molecular weight may be a polystyrene-equivalent molecular weight.

The dispersion index (Mw/Mn) of the iodine-containing polymer in this disclosure may be 1.5 or more, 2 or more, 3 or more, or 4 or more. The dispersion index (Mw/Mn) of the iodine-containing polymer in this disclosure may be 7.5 or less, 5 or less, 4 or less, or 3 or less.

[Structure of iodine-containing polymer]
The iodine-containing polymer may be linear or branched, but is preferably linear.

((1) Triiodophenyl Group-Containing Acrylic Monomer)
The iodine-containing polymer has a repeating unit derived from a triiodophenyl group-containing acrylic monomer (1). Conventionally, the iodine-containing polymer has a problem that its moldability is insufficient. The present inventors unexpectedly found that by selecting a triiodophenyl group-containing acrylic monomer (1) among iodine-containing monomers, it is possible to solve these problems while having a high refractive index.

In the present disclosure, monomer (1) has the following formula:
CH ₂ =C(-X ¹ )-C(=O)-Y ¹ -(L ¹ O) _p -TIP
[Wherein,
TIP is a triiodophenyl group;
^X1 is a hydrogen atom, a methyl group or a halogen atom;
^Y1 is -O- or -NH-;
Each ^L1 is independently an alkylene group having 1 to 10 carbon atoms;
p is 1 or more and 5 or less.
It may be expressed as:

TIP is a triiodophenyl group, which may be a 2,3,5-triiodophenyl group or a 2,4,6-triiodophenyl group, and is preferably a 2,4,6-triiodophenyl group.

^X1 is preferably a hydrogen atom or a methyl group.

It is preferred that ^Y1 is --O--.

The number of carbon atoms in L ¹ may be 1 or more, 2 or more, 3 or more, 4 or more, or 5 or more, and may be 10 or less, 8 or less, 6 or less, 4 or less, or 2 or less, for example, 4 or less.

p may be 1 or more, 2 or more, 3 or more, or 4, and may be 5 or less, 4 or less, 3 or less, 2 or less, or 1, for example, 3 or less.

Specific examples of -L ¹ O-, which is a repeating unit of -(L ¹ O) _p -, include:
-CH ₂ CH ₂ O-
_-CH2CH ( _CH3 )O-
_-CH2CH ( _{C2H5 )} O-
-CH ₂ C(CH ₃ ) ₂ O-
-CH ₂ CH ₂ CH ₂ CH ₂ O-
etc.

((2) Triiodophenyl Group-Free Acrylic Monomer)
The iodine-containing polymer may contain a repeating unit derived from a non-triiodophenyl group-containing acrylic monomer (2).

The triiodophenyl group-free acrylic monomer (2) does not have a triiodophenyl group. The triiodophenyl group-free acrylic monomer (2) may not have an iodophenyl group, and may not have an iodine atom.

In the present disclosure, monomer (2) has the following formula:
CH ₂ =C(-X ² )-C(=O)-Y ² -R
[Wherein,
^X2 is a hydrogen atom, a methyl group or a halogen atom;
^Y2 is -O- or -NH-
R is a hydrogen atom, a hydroxyl group, or an organic group having 1 to 30 carbon atoms.
It may be expressed as:

^X2 is preferably a hydrogen atom or a methyl group.

It is preferred that ^Y2 is --O--.

R may be an aliphatic or aromatic group, preferably an aliphatic group, and in particular an alkyl or (poly)oxyalkylene group.

When R is an alkyl group, the number of carbon atoms in R may be 1 or more, 2 or more, 3 or more, 5 or more, or 10 or more, and may be 30 or less, 25 or less, 20 or less, 15 or less, or 10 or less.

When R is a (poly)oxyalkylene group, the number of oxygen atoms in R may be 1 or more, 2 or more, or 3 or more, and may be 25 or less, 7 or less, or 5 or less.

When R is a (poly)oxyalkylene group, R has the formula:
-(R ¹ O) _q -R ²
[In the formula, R ¹ is independently an alkylene group having 1 to 10 carbon atoms, R ² is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and q is 1 to 100.]
It may be expressed as:

The number of carbon atoms in R ¹ may be 1 or more, 2 or more, 3 or more, or 5 or more, and may be 10 or less, 7 or less, 5 or less, or 3 or less.

q may be 1 or more, 3 or more, 5 or more, 10 or more, 25 or more, or 50 or more, and may be 100 or less, 80 or less, 60 or less, 40 or less, 20 or less, 10 or less, or 5 or less.

Specific examples of the repeating unit -R ¹ O- in -(R ¹ O) _q - include:
-CH ₂ CH ₂ O-
_-CH2CH ( _CH3 )O-
_-CH2CH ( _{C2H5 )} O-
-CH ₂ C(CH ₃ ) ₂ O-
-CH ₂ CH ₂ CH ₂ CH ₂ O-
etc.

When ^R2 is an alkyl group, the number of carbon atoms in ^R2 may be 1 or more, 2 or more, 3 or more, or 5 or more, and may be 10 or less, 7 or less, 5 or less, or 3 or less.

(Sulfur-containing structure)
The iodine-containing polymer in the present disclosure may have a sulfur atom. The refractive index of the iodine-containing polymer may be improved by having a sulfur atom. The sulfur atom may be present in the main chain or in a side chain, and is preferably present in the main chain.

(Structure derived from molecular weight control agent)
The iodine-containing polymer in the present disclosure may have a structure derived from a molecular weight control agent. The molecular weight control agent is an additive that can suppress polymerization and control the molecular weight range, and is typically a chain transfer agent. The molecular weight control agent is preferably an aromatic compound. By being aromatic, the refractive index of the iodine-containing polymer can be improved. Examples of the molecular weight control agent include various chain transfer agents, RAFT agents, NMP agents, ATRP agents, and TERP agents, and sulfur-containing chain transfer agents such as thiol-type chain transfer agents and RAFT agents are preferred.

The thiol-type chain transfer agent may be a monothiol compound, a dithiol compound, a trithiol compound, or a polythiol compound having a tetrathiol or higher, but is preferably a monothiol compound or a dithiol compound. The thiol-type chain transfer agent may be a thiol compound having a sulfur atom in addition to the thiol group. The thiol compound may be a molecule consisting of only carbon, hydrogen, and sulfur.

Specific examples of thiol-type chain transfer agents include aliphatic monothiol compounds such as methanethiol, ethanethiol, propanethiol, butanethiol, and cyclohexanethiol;

Methanedithiol, 1,2-ethanedithiol, 1,1-propanedithiol, 1,2-propanedithiol, 1,3-propanedithiol, 2,2-propanedithiol, 1,6-hexanedithiol, 1,2,3-propanetrithiol, 1,1-cyclohexanedithiol, 1,2-cyclohexanedithiol, 2,2-dimethylpropane-1,3-dithiol, 3,4-dimethoxybutane-1,2-dithiol, 2-methylcyclohexane-2,3-dithiol, 1,1-bis(mercaptomethyl)cyclohexane, thiomalic acid bis(2-mercaptoethyl ester), 2,3-dimercapto-1-propanol(2-mercaptoacetate), 2,3-dimercapto-1-propanol(3-mercaptopropionate), diethylene glycol bis( Aliphatic polythiol compounds such as 1,2-dimercaptopropyl methyl ether, 2,3-dimercaptopropyl methyl ether, 2,2-bis(mercaptomethyl)-1,3-propanedithiol, bis(2-mercaptoethyl)ether, ethylene glycol bis(2-mercaptoacetate), ethylene glycol bis(3-mercaptopropionate), trimethylolpropane bis(2-mercaptoacetate), trimethylolpropane bis(3-mercaptopropionate), pentaerythritol tetrakis(2-mercaptoacetate), pentaerythritol tetrakis(3-mercaptopropionate), and tetrakis(mercaptomethyl)methane;

Bis(mercaptomethyl)sulfide, bis(mercaptoethyl)sulfide, bis(mercaptopropyl)sulfide, bis(mercaptomethylthio)methane, bis(2-mercaptoethylthio)methane, bis(3-mercaptopropyl)methane, 1,2-bis(mercaptomethylthio)ethane, 1,2-(2-mercaptoethylthio)ethane, 1,2-(3-mercaptopropyl)ethane, 1,3-bis(mercapto 1,3-bis(2-mercaptoethylthio)propane, 1,3-bis(3-mercaptopropylthio)propane, 1,2-bis(2-mercaptoethylthio)-3-mercaptopropane, 2-mercaptoethylthio-1,3-propanedithiol, 1,2,3-tris(mercaptomethylthio)propane, 1,2,3-tris(2-mercaptoethylthio)propane, 1,2,3-tris(3-mercaptopropylthio)propane, mercaptopropylthio)propane, tetrakis(mercaptomethylthiomethyl)methane, tetrakis(2-mercaptoethylthiomethyl)methane, tetrakis(3-mercaptopropylthiomethyl)methane, bis(2,3-dimercaptopropyl)sulfide, 2,5-dimercapto-1,4-dithiane, bis(mercaptomethyl)disulfide, bis(mercaptoethyl)disulfide, bis(mercaptopropyl)disulfide, 4-mercaptomethyl-3,6-dithiaoctane-1,8-dithiol, bis(mercaptomethyl)-3,6,9-trithia-1,11-undecanedithiol, bis(1,3-dimercapto-2-propyl)sulfide, hydroxymethylsulfide bis(2-mercaptoacetate), hydroxymethylsulfide bis(3-mercaptopropionate), hydroxyethylsulfide bis(2-mercaptoacetate) ester), hydroxyethyl sulfide bis(3-mercaptopropionate), hydroxypropyl sulfide bis(2-mercaptoacetate), hydroxypropyl sulfide bis(3-mercaptopropionate), hydroxymethyl disulfide bis(2-mercaptoacetate), hydroxymethyl disulfide bis(3-mercaptopropionate), hydroxyethyl disulfide bis(2-mercaptoacetate), hydroxyethyl disulfide bis(3-mercaptopropionate), hydroxypropyl disulfide bis(2-mercaptoacetate), hydroxypropyl disulfide bis(3-mercaptopropionate), 2-mercaptoethyl ether bis(2-mercaptoacetate), 2-mercaptoethyl ether bis(3-mercaptopropionate), 1,4-dithiane-2,5-diol bis(2 -mercaptoacetate), 1,4-dithiane-2,5-diol bis(3-mercaptopropionate), thioglycolic acid bis(2-mercaptoethyl ester), thiodipropionic acid bis(2-mercaptoethyl ester), 4,4'-thiodibutyric acid bis(2-mercaptoethyl ester), dithiodiglycolic acid bis(2-mercaptoethyl ester), dithiodipropionic acid bis(2-mercaptoethyl ester), 4,4'-dithiodibutyric acid bis(2-mercaptoethyl ester), thiodiglycolic acid bis(2,3-dimercaptopropyl ester), thiodipropionic acid bis(2,3-dimercaptopropyl ester), dithiodiglycolic acid bis(2,3-dimercaptopropyl ester), dithiodipropionic acid bis(2,3-dimercaptopropyl ester), etc., aliphatic thiols containing sulfur atoms in addition to mercapto groups;

Aromatic monothiol compounds such as benzenethiol, o-methyl-α-toluenethiol, o-toluenethiol, m-toluenethiol, p-toluenethiol, 1-naphthalenethiol, and 2-naphthalenethiol;

1,2-dimercaptobenzene, 1,3-dimercaptobenzene, 1,4-dimercaptobenzene, 1,2-bis(mercaptomethyl)benzene, 1,3-bis(mercaptomethyl)benzene, 1,4-bis(mercaptomethyl)benzene, 1,2-bis(mercaptoethyl)benzene, 1,3-bis(mercaptoethyl)benzene, 1,4-bis(mercaptoethyl)benzene, 1,2,3-trimercaptobenzene, 1,2,4-trimercaptobenzene, 1,3,5-trimercaptobenzene, 1,2,3-tris(mercaptomethyl)benzene, 1,2, Aromatic polythiols such as 4-tris(mercaptomethyl)benzene, 1,3,5-tris(mercaptomethyl)benzene, 1,2,3-tris(mercaptoethyl)benzene, 1,2,4-tris(mercaptoethyl)benzene, 1,3,5-tris(mercaptoethyl)benzene, 2,5-toluenedithiol, 3,4-toluenedithiol, 1,3-di(p-methoxyphenyl)propane-2,2-dithiol, 1,3-diphenylpropane-2,2-dithiol, phenylmethane-1,1-dithiol, and 2,4-di(p-mercaptophenyl)pentane;

1,2-bis(mercaptomethylenethio)benzene, 1,3-bis(mercaptomethylenethio)benzene, 1,4-bis(mercaptomethylenethio)benzene, 1,2-bis(mercaptoethylenethio)benzene, 1,3-bis(mercaptoethylenethio)benzene, 1,4-bis(mercaptoethylenethio)benzene, 1,2-bis(mercaptopropylenethio)benzene, 1,3-bis(mercaptopropylenethio)benzene, 1,4-bis(mercaptopropylenethio)benzene, 1,2-bis(mercaptoethylenethiomethylene)benzene, 1, 3-bis(mercaptoethylenethiomethylene)benzene, 1,4-bis(mercaptoethylenethiomethylene)benzene, 1,2-bis(mercaptopropylenethiomethylene)benzene, 1,3-bis(mercaptopropylenethiomethylene)benzene, 1,4-bis(mercaptopropylenethiomethylene)benzene, bis(4-mercaptophenyl)sulfide, bis(3-mercaptophenyl)sulfide, 4,4'-oxybisbenzenethiol, 4,4'-biphenyldithiol, 1,2-bis(mercaptomethyleneoxy)benzene, 1,3-bis(methylphenyl)sulfide 1,4-bis(mercaptomethyleneoxy)benzene, 1,2-bis(mercaptoethyleneoxy)benzene, 1,3-bis(mercaptoethyleneoxy)benzene, 1,4-bis(mercaptoethyleneoxy)benzene, 1,2-bis(mercaptoethyleneoxymethylene)benzene, 1,3-bis(mercaptoethyleneoxymethylene)benzene, 1,4-bis(mercaptoethyleneoxymethylene)benzene, 1,2-bis(mercaptopropyleneoxymethylene)benzene, 1,3-bis(mercaptopropylene Aromatic polythiol compounds containing sulfur atoms in addition to mercapto groups, such as 1,4-bis(mercaptopropyleneoxymethylene)benzene, 1,3,5-trimercaptobenzene, 1,2,3-tris(mercaptomethylthio)benzene, 1,2,4-tris(mercaptomethylthio)benzene, 1,3,5-tris(mercaptomethylthio)benzene, 1,2,3-tris(mercaptoethylthio)benzene, 1,2,4-tris(mercaptoethylthio)benzene, and 1,3,5-tris(mercaptoethylthio)benzene;

Heterocyclic compounds containing a sulfur atom in addition to a mercapto group, such as 3,4-thiophenedithiol and 2,5-dimercapto-1,3,4-thiadiazole;

2-mercaptoethanol, 3-mercapto-1,2-propanediol, glycerin di(mercaptoacetate), 1-hydroxy-4-mercaptocyclohexane, 2,4-dimercaptophenol, 2-mercaptohydroquinone, 4-mercaptophenol, 3,4-dimercapto-2-propanol, 1,3-dimercapto-2-propanol, 2,3-dimercapto-1-propanol, 1,2-dimercapto-1,3-butanediol, pentaerythritol tris(3-mercaptoprop pentaerythritol pentakis(3-mercaptopropionate), pentaerythritol mono(3-mercaptopropionate), pentaerythritol bis(3-mercaptopropionate), pentaerythritol tris(thioglycolate), dipentaerythritol pentakis(3-mercaptopropionate), hydroxymethyl-tris(mercaptoethylthiomethyl)methane, 1-hydroxyethylthio-3-mercaptoethylthiobenzene, and other compounds that contain a hydroxy group in addition to a mercapto group, as well as derivatives thereof. These may be used alone or in combination of two or more.

Specific examples of RAFT agents include dithioesters such as 2-cyano-2-propyl benzodithioate and 4-cyano-4-(phenylcarbonothioylthio)pentanoic acid; trithiocarbonates such as 2-cyano-2-propyl dodecyl trithiocarbonate, 4-cyano-4-[(dodecylsulfanylthiocarbonyl)sulfanyl]pentanoic acid, 2-(dodecylthiocarbonothioylthio)-2-methylpropionic acid, and cyanomethyl dodecyl trithiocarbonate; dithiocarbamates such as cyanomethyl methyl(phenyl)carbamodithioate; and disulfides such as bis(thiobenzoyl) disulfide and bis(dodecylsulfanylthiocarbonyl) disulfide. These may be used alone or in combination of two or more.

(Structures derived from other raw materials)
The iodine-containing polymer of the present disclosure may have a structure derived from other raw materials in addition to the above. Specific examples of other raw materials include styrene-based monomers such as styrene, p-methylstyrene, α-methylstyrene, halogenated styrene, vinylbenzoic acid, 4-vinylbenzenesulfonic acid, 4-vinylbenzenesulfonic acid ester, and 4-vinylbenzenesulfonic acid amide; amide group-containing vinyl monomers such as (meth)acrylamide, N-methyl(meth)acrylamide, N-ethyl(meth)acrylamide, N,N-dimethyl(meth)acrylamide, and N,N-dimethylaminopropyl(meth)acrylamide; methyl(meth)acrylate, ethyl(meth)acrylate, propyl(meth)acrylate, butyl(meth)acrylate, and 2-(meth)acrylic acid. Examples of such monomers include (meth)acrylates and (meth)acrylamide monomers such as ethylhexyl, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, glycidyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, N,N-diethylaminoethyl (meth)acrylate, N-t-butylaminoethyl (meth)acrylate, and polyethylene glycol (meth)acrylic; nitrile group-containing vinyl monomers such as (meth)acrylonitrile; and other monomers such as vinyl halides, vinylidene halides, and vinyl acetate. These monomers may be used alone or in combination of two or more.

[Composition of iodine-containing polymer]
The content of the repeating unit derived from the monomer (1) in the iodine-containing polymer may be 20% by weight or more, 30% by weight or more, 40% by weight or more, 50% by weight or more, 60% by weight or more, 70% by weight or more, 80% by weight or more, 90% by weight or more, or 95% by weight or more, preferably 70% by weight or more. The content of the repeating unit derived from the monomer (1) in the iodine-containing polymer may be 95% by weight or less, 85% by weight or less, 75% by weight or less, 65% by weight or less, 55% by weight or more, or 45% by weight or less. From the viewpoint of improving the refractive index, the larger the amount of the monomer (1), the more preferable.

The content of the repeating unit derived from monomer (2) in the iodine-containing polymer may be 2.0% by weight or more, 4.0% by weight or more, 6.0% by weight or more, 8.0% by weight or more, 10% by weight or more, 15% by weight or more, or 20% by weight or more. The content of the repeating unit derived from monomer (2) in the iodine-containing polymer may be 50% by weight or less, 40% by weight or less, 30% by weight or less, 20% by weight or less, 10% by weight or less, or 7.5% by weight or less. The presence of the repeating unit derived from monomer (2) makes it possible to form a high molecular weight polymer, and the density of the synthesized polymer increases, thereby increasing the refractive index. It may also be preferable from the viewpoint of moldability.

The content of the structure derived from the molecular weight control agent in the iodine-containing polymer may be 1.0% by weight or more, 3.0% by weight or more, 5.0% by weight or more, or 10% by weight or more, and is preferably 3% by weight or more. The content of the structure derived from the molecular weight control agent in the iodine-containing polymer may be 50% by weight or less, 40% by weight or less, 30% by weight or less, or 25% by weight or less, and is preferably 40% by weight or less.

The content of structures derived from other raw materials in the iodine-containing polymer may be 1.0% by weight or more, 3.0% by weight or more, 5.0% by weight or more, or 10% by weight or more. The content of structures derived from other raw materials in the iodine-containing polymer may be 30% by weight or less, 20% by weight or less, or 10% by weight or less.

The iodine content in the iodine-containing polymer may be 10% by weight or more, 25% by weight or more, 30% by weight or more, 35% by weight or more, 40% by weight or more, or 45% by weight or more, and is preferably 30% by weight or more. The iodine content in the iodine-containing polymer may be 55% by weight or less, 50% by weight or less, or 45% by weight or less.

The sulfur content in the iodine-containing polymer may be 1.0% by weight or more, 2.0% by weight or more, 3.0% by weight or more, 4.0% by weight or more, 5.0% by weight or more, or 7.5% by weight or more, and is preferably 2.0% by weight or more. The sulfur content in the iodine-containing polymer may be 30% by weight or less, 20% by weight or less, 15% by weight or less, or 10% by weight or less, and is preferably 10% by weight or less.

The content of the repeating unit derived from monomer (1) may be 2.0 molar parts or more, 3.0 molar parts or more, 5.0 molar parts or more, 10 molar parts or more, 15 molar parts or more, or 20 molar parts or more, and preferably 3 molar parts or more, per 1 molar part of the structure derived from the molecular weight control agent in the iodine-containing polymer. The content of the repeating unit derived from monomer (1) may be 50 molar parts or less, 45 molar parts or less, 40 molar parts or less, 35 molar parts or less, 30 molar parts or less, or 25 molar parts or less, and preferably 40 molar parts or less, per 1 molar part of the structure derived from the molecular weight control agent.

The content of the repeating unit derived from monomer (2) in the iodine-containing polymer may be 0.2 molar parts or more, 0.3 molar parts or more, 0.5 molar parts or more, 1.0 molar parts or more, 1.5 molar parts or more, or 2 molar parts or more, preferably 0.3 molar parts or more, per 1 molar part of the structure derived from the molecular weight control agent. The content of the repeating unit derived from monomer (1) may be 5.0 molar parts or less, 4.5 molar parts or less, 4.0 molar parts or less, 3.5 molar parts or less, 3.0 molar parts or less, or 2.5 molar parts or less, preferably 4.0 molar parts or less, per 1 molar part of the structure derived from the molecular weight control agent.

The content of the repeating unit derived from monomer (2) may be 0.01 molar parts or more, 0.02 molar parts or more, 0.03 molar parts or more, 0.05 molar parts or more, 0.1 molar parts or more, 0.15 molar parts or more, or 0.2 molar parts or more, preferably 0.03 molar parts or more, for example 0.1 molar parts or more, relative to 1 molar part of the repeating unit derived from monomer (1) in the iodine-containing polymer. The amount of monomer (2) used may be 0.5 molar parts or less, 0.45 molar parts or less, 0.4 molar parts or less, 0.35 molar parts or less, 0.3 molar parts or less, 0.25 molar parts or less, 0.15 molar parts or less, or 0.10 molar parts or less, preferably 0.4 molar parts or less, relative to 1 molar part of monomer (1).

By containing each component in the above range, the iodine-containing polymer can have a high refractive index and moldability, while also providing a good balance of excellent solubility, film-forming properties, heat resistance, and transparency.

[Method for producing iodine-containing polymer]
In the method for producing the iodine-containing polymer of the present disclosure, the iodine-containing polymer can be obtained by a step of polymerizing the above-mentioned monomers as raw materials.
The method for producing an iodine-containing polymer according to the present disclosure includes the steps of:
The method may include a step of polymerizing the monomer in the presence of a molecular weight control agent. By polymerizing the monomer in the presence of a molecular weight control agent, it becomes easy to control the molecular weight within the above-mentioned range.

The amount of the raw materials used can be appropriately changed so that the above-mentioned iodine-containing polymer can be obtained. The amount of monomer (1) used can be 2.0 molar parts or more, 3.0 molar parts or more, 5.0 molar parts or more, 10 molar parts or more, 15 molar parts or more, or 20 molar parts or more, and is preferably 3 molar parts or more, for example 10 molar parts or more, relative to 1 molar part of the molecular weight control agent. The amount of monomer (1) used can be 50 molar parts or less, 45 molar parts or less, 40 molar parts or less, 35 molar parts or less, 30 molar parts or less, or 25 molar parts or less, and is preferably 40 molar parts or less, relative to 1 molar part of the molecular weight control agent. For example, by increasing the amount of the molecular weight control agent, polymerization can be suppressed and an increase in molecular weight can be suppressed.

The amount of monomer (2) used may be 0.2 molar parts or more, 0.3 molar parts or more, 0.5 molar parts or more, 1.0 molar parts or more, 1.5 molar parts or more, or 2 molar parts or more relative to 1 molar part of molecular weight control agent, and is preferably 0.3 molar parts or more, for example 1 molar part or more. The amount of monomer (2) used may be 5.0 molar parts or less, 4.5 molar parts or less, 4.0 molar parts or less, 3.5 molar parts or less, 3.0 molar parts or less, or 2.5 molar parts or less relative to 1 molar part of molecular weight control agent, and is preferably 4.0 molar parts or less. For example, by increasing the amount of molecular weight control agent, polymerization can be suppressed and an increase in molecular weight can be suppressed.

The amount of monomer (2) used may be 0.01 molar parts or more, 0.02 molar parts or more, 0.03 molar parts or more, 0.05 molar parts or more, 0.1 molar parts or more, 0.15 molar parts or more, or 0.2 molar parts or more, and is preferably 0.03 molar parts or more, for example 0.1 molar parts or more, relative to 1 molar part of monomer (1). The amount of monomer (2) used may be 0.5 molar parts or less, 0.45 molar parts or less, 0.4 molar parts or less, 0.35 molar parts or less, 0.3 molar parts or less, 0.25 molar parts or less, 0.15 molar parts or less, or 0.10 molar parts or less, and is preferably 0.4 molar parts or less, relative to 1 molar part of monomer (1). The presence of monomer (2) may improve film-forming properties.

In the present disclosure, the polymerization method is not particularly limited, and can be performed by a known polymerization method such as bulk polymerization, solution polymerization, suspension polymerization, emulsion polymerization, etc., but solution polymerization is preferred. Also, a known polymerization method such as radical polymerization, anionic polymerization, cationic polymerization, etc. can be selected, but radical polymerization is preferably selected. An appropriate polymerization method can be selected depending on the type of monomer, polymerization temperature, etc.

In the present disclosure, an appropriate polymerization initiator can be selected and used depending on the type of monomer, polymerization temperature, etc. Examples of polymerization initiators include azo-based initiators such as 2,2'-azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile), 2,2'-azobis(2,2-dimethylvaleronitrile), 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile), 1,1'-azobis(cyclohexane-1-carbonitrile), and 2,2'-azobis(2-amidinopropane)dihydrochloride; and peroxide-based initiators such as benzoyl peroxide, di-t-butyl hydroperoxide, t-butyl hydroperoxide, cumyl peroxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, benzoyl peroxide, dicumyl peroxide, ethyl 3,3-di(t-amylperoxy)butyrate, potassium sulfate, and ammonium persulfate. These may be used alone or in combination of two or more types.

When polymerization is carried out by solution polymerization, an appropriate solvent is selected taking into consideration the solubility of the monomer and radical initiator, the polymerization temperature, etc., and the polymerization can be carried out in that solvent. Examples of solvents include DMF, N-methyl-2-pyrrolidone, acetone, THF, benzene, toluene, ethylbenzene, xylene, chlorobenzene, methyl ethyl ketone, ethyl lactate, isopropyl alcohol, etc. These may be used alone or in combination of two or more.

The polymerization temperature may be any temperature at which the polymerization initiator decomposes and polymerization begins, and may be, for example, 0°C or higher, 20°C or higher, 40°C or higher, 60°C or higher, or 70°C or higher, and is preferably 40°C or higher and may be 100°C or lower, 90°C or lower, 80°C or lower, or 70°C or lower.

The optimal polymerization time can be determined depending on the selected monomer, polymerization initiator, polymerization temperature, etc., but may be, for example, 1 hour or more, 5 hours or more, 10 hours or more, 15 hours or more, or 20 hours or more, and may be 72 hours or less, 60 hours or less, 48 hours or less, 36 hours or less, or 24 hours or less.

The amount of polymerization initiator used may vary depending on the type of monomer and the type of initiator, but may be, for example, 0.1 mol% or more, 1 mol% or more, 3 mol% or more, 5 mol% or more, 10 mol% or more, 15 mol% or more, 20 mol% or more, or 25 mol% or more, and may be 50 mol% or less, 40 mol% or less, 30 mol% or less, 20 mol% or less, or 10 mol% or less, based on the total amount of monomers used.

The amount of polymerization solvent used is not particularly limited, but may be in a range such that the raw material concentration is 5% by weight or more, 10% by weight or more, 15% by weight or more, or 20% by weight or more, and 50% by weight or less, 40% by weight or less, 30% by weight or less, or 20% by weight or less.

<Optical components and their manufacturing methods>
The optical part includes an optical material containing the above-mentioned iodine-containing polymer. Examples of the optical part include a coating, a film, a sheet, a prism, a lens, a fiber, and the like. Since the optical material of the present disclosure has excellent moldability, the optical part may be produced by molding (e.g., thermoforming) the optical material. That is, the optical part may be a molded product of the optical material.

The optical components disclosed herein can be handled as free-standing films after molding. This is because the iodine-containing polymer has excellent flexibility and mechanical strength, and can be easily separated from the substrate.

The manufacturing method of the optical component in the present disclosure may include a step of molding the optical material. The molding process may utilize various molding devices such as compression molding, extrusion molding, and injection molding. The molding temperature is not particularly limited as long as it is a molding process, but may be a temperature equal to or higher than the temperature at which the optical material softens at normal pressure and equal to or lower than the decomposition temperature. The molding temperature may be, for example, 120°C or higher, 140°C or higher, 160°C or higher, 180°C or higher, or 200°C or higher, and may be 300°C or lower, 275°C or lower, 250°C or lower, 225°C or lower, 200°C or lower, or 175°C or lower.

The method for producing an optical component according to the present disclosure may include a step of forming a film of an optical material on a substrate by the above-mentioned molding process, and separating the film from the substrate. The method of separation is not particularly limited, and examples thereof include a method of physically gripping and peeling off a part of the film or substrate, and a method of separating the film from the substrate using a sharp tool such as a blade.

It is also possible to form an optical component by dissolving an optical material in a solvent, applying it to a substrate, and then drying the solvent. When applying the optical material to a substrate, it may be used as a solution containing a solvent that dissolves the iodine-containing polymer. The type of solvent is not particularly limited as long as it dissolves the iodine-containing polymer, but for example, organic solvents such as THF, chloroform, DMF, and DMSO can be used. The concentration of the iodine-containing polymer in the liquid may be 0.01 wt% or more, 0.1 wt% or more, 0.5 wt% or more, or 1 wt% or more, and may be 5 wt% or less, 3 wt% or less, 1.5 wt% or less, or 0.5 wt% or less. A coating or the like may be obtained by applying a solution containing an iodine polymer to a substrate and removing the solvent as necessary. The application method may be any commonly used method such as dip coating, spray coating, flow coating, shower coating, roll coating, spin coating, gravure coating, microgravure coating, comma roll coating, Mayer bar coating, slot bicoat, air knife coating, lip coating, kiss coating, brush coating, etc. The removal of the solvent is not particularly limited, but may be carried out at, for example, 0 to 200°C.

The type of substrate is not particularly limited and may be resin, glass, metal, ceramic, etc.

The film thickness of the optical component may be 0.1 μm or more, 1 μm or more, or 3 μm or more, and may be 1 m or less, 500 μm or less, or 200 μm or less.

<Optical article having optical component>
Examples of optical articles having optical components such as the above-mentioned coatings include, but are not limited to, optical devices such as high refractive index light emitting diodes (LEDs) and image sensors; high refractive index materials such as anti-reflection films, lenses, and lens coatings; and optical instruments such as telescopes, binoculars, microscopes, cameras, endoscopes (fiberscopes), planetariums, length measuring instruments, comparators, range finders, spectrometers, interferometers, and polarimeters.

Although the embodiments have been described above, it will be understood that various changes in form and details are possible without departing from the spirit and scope of the claims.

The following describes in detail the embodiments of the present disclosure with reference to examples, but the present disclosure is not limited to these examples.

The test method is as follows:

<NMR Measurement>
The compounds were identified using NMR. A 400 MHz-NMR JOEL ECS-400K manufactured by JEOL Ltd. or a 400 MHz-NMR JOEL ECZ-400 manufactured by JEOL Ltd. was used.

<SEC Measurement>
The experiment was carried out using the following equipment and conditions.
Tosoh Corporation HLC-8320GPC
Column: TSKgel SuperMultiporeHZ-M x 2 (4.6mmI.D. x 15cm x 2)
Standard: Polystyrene SRM706 (NIST)
Eluent: THF
Detector: RI; Polarity (+), Response (0.5s)
UV; wavelength (254nm), polarity (+), response (0.5s)

<Refractive index>
The refractive index of the iodine-containing polymer was measured by forming a film of the iodine-containing polymer on a silicon wafer, measuring 30 points with a laser having a wavelength of 632 nm using an ellipsometer (SE-101 manufactured by Photonic Lattice Co., Ltd.), and averaging the measurements. The results are shown in the table below.

<Heat resistance>
Using a TGA measuring device (Shimadzu Model TGA-50/50H), measurements were performed in a nitrogen gas atmosphere at a temperature increase rate of 10° C./min in the temperature range from 25° C. to 450° C. The temperature _Td at which a 5% weight loss was observed is shown in the table below.

<Molding processability test>
The obtained iodine-containing polymer was molded using a vacuum press (manufactured by Imoto Manufacturing, manual hydraulic vacuum heating press). The resin was placed in a mold, sandwiched between metal plates (aluminum plates), and placed in a vacuum press, where the pressure was reduced to 0.1 MPa or less, and then heated until the molding temperature reached 200°C. After reaching the molding temperature, the press pressure was increased to 2 MPa and heated for 2 minutes. The press pressure was then increased over 3 minutes, and molding was performed while maintaining 15 MPa for 5 minutes. After molding, the pressure was returned to atmospheric pressure and cooled to room temperature.
The moldability was evaluated according to the following criteria.
◯: A uniform film can be formed, and the obtained film can be separated from the substrate. ×: An uneven film is formed, and/or the film is damaged when attempting to separate it from the substrate, making it impossible to separate the film.

１００ｍｌのナスフラスコに、2,4,6-triiodophenol 10mmol(4,71g)、塩基触媒として、炭酸セシウム12mmol(3.90g)、触媒として、臭化テトラブチルアンモニウム（tetrabutylammonium bromide,TBAB）0.5mmol(0.16g)、そして溶媒としてN-メチルピロリドン（N-Methyl-pyrolidone, NMP）２０ｍｌを６０℃で１時間かけて予備攪拌後、２－クロロエタノール(2-chloroethanol) 15mmol(1.2g)を加えてさらに６０℃で２４時間攪拌した。黄色固体を得た。エバポレーションして酢酸エチルを加えた。濾過して塩を取り除き、分液操作（1N HCl, sat NaHCO3, sat NaCl）を各3回行った。有機層にMgSO4を入れて脱水をして減圧乾燥し、黄色粉末固体（2,4,6-triiodophonoxyethanol(TIPE)）を4.46g得た。収率は８１％であった。 [Synthesis of Monomer (1) Precursor (TIPE)]

In a 100 ml eggplant flask, 10 mmol (4.71 g) of 2,4,6-triiodophenol, 12 mmol (3.90 g) of cesium carbonate as a base catalyst, 0.5 mmol (0.16 g) of tetrabutylammonium bromide (TBAB) as a catalyst, and 20 ml of N-Methyl-pyrolidone (NMP) as a solvent were pre-stirred at 60°C for 1 hour, and then 15 mmol (1.2 g) of 2-chloroethanol was added and stirred at 60°C for another 24 hours. A yellow solid was obtained. Evaporation was performed and ethyl acetate was added. The salt was removed by filtration, and separation operations (1N HCl, sat. NaHCO3, sat. NaCl) were performed three times each. The organic layer was dehydrated with MgSO4 and dried under reduced pressure to obtain 4.46 g of a yellow powder solid (2,4,6-triiodophonoxyethanol (TIPE)). The yield was 81%.

１００ｍｌのナスフラスコに、前記の合成で得られた2,4,6-triiodophonoxyethanol(TIPE)50mmol(25.7g)、トリエチルアミン70mmol(7.08g)、溶媒として、ジクロロメタン（DCM）150mlを入れて、氷浴でジクロロメタン（DCM）7mlで希釈した Acryl chloride75mmol(6.74g)を添加して、室温で８時間攪拌した。黄色固体を得た。カラムクロマトグラフィーにて、クロロホルム：ヘキサン＝３：１の展開溶媒で溶出させて、減圧乾燥して、白色固体粉末（2,4,6-triiodo2-Phenoxyethyl Acrylate (TIPEA)）14.89ｇを得た。収率は５２％であった。 [Synthesis of Monomer (1) (TIPEA)]

In a 100 ml eggplant flask, 50 mmol (25.7 g) of 2,4,6-triiodophonoxyethanol (TIPE) obtained in the above synthesis, 70 mmol (7.08 g) of triethylamine, and 150 ml of dichloromethane (DCM) as a solvent were placed, and 75 mmol (6.74 g) of acrylic chloride diluted with 7 ml of dichloromethane (DCM) was added in an ice bath and stirred at room temperature for 8 hours. A yellow solid was obtained. The product was eluted by column chromatography with a developing solvent of chloroform:hexane = 3:1, and dried under reduced pressure to obtain 14.89 g of white solid powder (2,4,6-triiodo2-phenyloxyethyl acrylate (TIPEA)). The yield was 52%.

１０ｍｌのナスフラスコに、前記の合成で得られた2,4,6-triiodo2-Phenoxyethyl Acrylate (TIPEA)6mmol(3.41g)、重合開始剤として、Azobisisobutyronitrile(AIBN)0.18mmol(0.029g)、溶媒として、ジメチルホルムアミド（DMF）1.8mlを入れて、脱気風乾を行い、６０℃オイルバス中で２０時間攪拌した。ジエチルエーテルで再沈殿してメンブレンろ過した後、減圧乾燥して、含ヨウ素ポリマー３ｇを得た。収率は８８％であった。 [Example 1: Synthesis of iodine-containing polymer (poly(TIPEA))]

In a 10 ml eggplant flask, 6 mmol (3.41 g) of 2,4,6-triiodo2-phenyloxyethyl acrylate (TIPEA) obtained in the above synthesis, 0.18 mmol (0.029 g) of azobisisobutyronitrile (AIBN) as a polymerization initiator, and 1.8 ml of dimethylformamide (DMF) as a solvent were placed, degassed and air-dried, and stirred in a 60°C oil bath for 20 hours. After reprecipitation with diethyl ether and membrane filtration, the mixture was dried under reduced pressure to obtain 3 g of iodine-containing polymer. The yield was 88%.

重合管に前記の合成で得られたTIPEA 0.95mmol, 2-(2-Ethoxyethoxy)ethyl Acrylate(EEA) 0.05mmol, THF 0.3ml, AIBN (TIP-ACとEEAの合計量に対して3mol%),を入れて脱気封管を行い60℃オイルバス中で20h攪拌した。THFで希釈後、ジエチルエーテルで再沈殿してメンブレン濾過した後、減圧乾燥して含ヨウ素ポリマーを得た。得られた含ヨウ素ポリマーについて、熱重量測定、溶解性試験、屈折率測定を行った。 [Example 2: Synthesis of iodine-containing polymer (poly(TIPEA-co-EEA))]

0.95mmol of TIPEA obtained by the synthesis above, 0.05mmol of 2-(2-Ethoxyethoxy)ethyl Acrylate (EEA), 0.3ml of THF, and AIBN (3mol% based on the total amount of TIP-AC and EEA) were placed in a polymerization tube, degassed and sealed, and stirred for 20h in a 60℃ oil bath. After dilution with THF, the mixture was reprecipitated with diethyl ether, filtered through a membrane, and dried under reduced pressure to obtain an iodine-containing polymer. The obtained iodine-containing polymer was subjected to thermogravimetry, solubility test, and refractive index measurement.

[Examples 3 to 5: Synthesis of iodine-containing polymer (poly(TIPEA-co-EEA))]
Poly(TIPEA-co-EEA) was synthesized in the same manner as in Example 2, except that the molar ratio of TIPEA to EEA was changed as shown in the table below.

で表されるTIPA（triiodophenyl acrylate）を同モル量用いた以外は、実施例１と同様にして、poly(TIPA）を合成した。なお、TIPAは特開2022-131503号公報に記載の方法で合成した。 [Comparative Example 1: Synthesis of iodine-containing polymer (poly(TIPA))]
Instead of TIPEA,

Poly(TIPA) was synthesized in the same manner as in Example 1, except that the same molar amount of TIPA (triiodophenyl acrylate) represented by the formula (1) was used. TIPA was synthesized by the method described in JP-A-2022-131503.

で表されるTIPAを同モル量用いた以外は、実施例３と同様にして、poly(TIPA-EEA）を合成した。 [Comparative Example 2: Synthesis of iodine-containing polymer poly(TIPA-EEA)]
Instead of TIPEA,

Poly(TIPA-EEA) was synthesized in the same manner as in Example 3, except that the same molar amount of TIPA represented by the following formula was used:

[result]
The composition and measurement results of the obtained iodine-containing polymer are shown in the table below.
[Table 1]

The iodine-containing polymers of the present disclosure can be used in optical devices such as high refractive index light-emitting diodes (LEDs) and image sensors, high refractive index materials such as anti-reflection films, lens materials, and high refractive index polymer materials such as lens coatings, and optical instruments such as telescopes, binoculars, microscopes, cameras, endoscopes (fiberscopes), planetariums, length measuring instruments, comparators, range finders, spectrometers, interferometers, and polarimeters.

Claims (15)

formula:
CH ₂ =C(-X ¹ )-C(=O)-Y ¹ -(L ¹ O) _p -TIP
[Wherein,
TIP is a triiodophenyl group;
^X1 is a hydrogen atom, a methyl group or a halogen atom;
^Y1 is -O- or -NH-;
Each ^L1 is independently an alkylene group having 1 to 10 carbon atoms;
p is 1 or more and 5 or less.
An optical material comprising an iodine-containing polymer including a repeating unit derived from a triiodophenyl group-containing acrylic monomer (1) represented by the following formula: Each ^L1 is independently an alkylene group having 1 to 4 carbon atoms;
2. The optical material according to claim 1, wherein p is 1 to 3. -Y ¹ -(L ¹ O) _p - is a group represented by the formula:
-O-CH ₂ CH ₂ -O-
The optical material according to claim 1 , The optical material according to claim 1, which is for molding. The optical material according to claim 1, which is for forming a free-standing film. The iodine-containing polymer has the following formula:
CH ₂ =C(-X ² )-C(=O)-Y ² -R
[In the formula, TIP is the triiodophenyl group,
^X2 is a hydrogen atom, a methyl group or a halogen atom;
^Y2 is -O- or -NH-;
R is an organic group having 2 to 30 carbon atoms.
The optical material according to claim 1 , which has a repeating unit derived from a triiodophenyl group-free acrylic monomer (2) represented by the following formula: The optical material according to claim 6, wherein R is an alkylene group or a (poly)oxyalkylene group. The optical material according to claim 1, wherein the content of the repeating units derived from the monomer (1) in the iodine-containing polymer is 75% by weight or more. The optical material according to claim 1, wherein the iodine-containing polymer has a structure derived from a molecular weight control agent. An optical component comprising the optical material according to any one of claims 1 to 9. The optical component according to claim 10, which is a molded product of the optical material. The optical component according to claim 10, which is a free-standing film. A method for manufacturing an optical component, comprising a step of molding the optical material according to any one of claims 1 to 9. The method for manufacturing an optical component according to claim 13, comprising a step of forming a film of an optical material by performing the molding process on a substrate and separating the film from the substrate. An optical article comprising the optical component according to claim 10.