JP2021091757A - Episulfide composition, cured article, and optical material - Google Patents

Abstract

To provide an episulfide composition excellent in controllability of a polymerization rate of an episulfide compound, and, capable of suppressing deterioration of characteristic of a resin obtained by polymerization of the episulfide compound.SOLUTION: An episulfide composition containing an episulfide compound containing an episulfide ring and not containing a hydroxyl group, and a radical scavenger containing a hydroxyl group.SELECTED DRAWING: None

Description

The present disclosure relates to episulfide compositions, cured products, and optical materials.

Compared to inorganic lenses, plastic lenses are lighter, harder to break, and can be dyed. Therefore, in recent years, plastic lenses have rapidly become widespread in applications such as spectacle lenses and camera lenses.
Among resin-made optical materials typified by plastic lenses, an optical material obtained by polymerizing an episulfide compound is known to have a high refractive index (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2002-194083

However, the episulfide compound as a monomer (for example, the episulfide compound described in Patent Document 1) has room for improvement in controlling the polymerization rate.

When the polymerization of the episulfide compound proceeds excessively, it is conceivable to add some additive to the episulfide compound to control the polymerization rate.
However, when the solubility of the additive in the episulfide compound is low, the amount of the additive used is limited, so that there is a problem that the control of the polymerization rate may be insufficient.

On the other hand, when an additive is added to the episulfide compound, the characteristics of the resin obtained by the polymerization of the episulfide compound may deteriorate (for example, the color tone of the resin may change, turbidity may occur, etc.). Therefore, when an additive is added to the episulfide compound, it is also required to suppress the deterioration of the characteristics of the resin.

This disclosure has been made in view of the above circumstances.
An object of the present disclosure is an episulfide composition having excellent controllability of the polymerization rate of the episulfide compound and capable of suppressing deterioration of the characteristics of the resin obtained by the polymerization of the episulfide compound, a cured product of the episulfide composition, and the curing. It is to provide an optical material including an object.

Means for solving the above problems include the following aspects.
<1> An episulfide composition containing an episulfide compound containing an episulfide ring and not containing a hydroxyl group, and a radical scavenger containing a hydroxyl group.
<2> The episulfide composition according to <1>, wherein the episulfide compound containing an episulfide ring and not containing a hydroxyl group contains a compound containing an episulfide ring and at least one of a sulfide bond and a disulfide bond.
<3> The episulfide composition according to <1> or <2>, wherein the episulfide compound containing an episulfide ring and not containing a hydroxyl group contains a compound represented by the following formula (1).

In the formula (1), R ^{1 to} R ⁵ are monovalent hydrocarbon groups that may be independently substituted with a hydrogen atom or a substituent other than a hydroxyl group, and m is 0 to 3. It is an integer, and n is an integer of 2 to 4.
When n is 2, L is an n-valent linking group, sulfide bond, or disulfide bond containing at least one of a sulfide bond and a disulfide bond and a hydrocarbon group and not containing a hydroxyl group.
When n is 3 or 4, L is an n-valent linking group containing at least one of a sulfide bond and a disulfide bond and a hydrocarbon group and containing no hydroxyl group.
Each of a plurality of R ^{1 to} R ⁵ and m may be the same or different.

<4> The episulfide composition according to <3>, wherein the n is 2 and the L is a disulfide bond in the formula (1).
<5> The episulfide composition according to any one of <1> to <4>, wherein the radical scavenger containing a hydroxyl group further contains at least one of a benzene ring and an episulfide ring.
<6> The episulfide composition according to any one of <1> to <5>, wherein the radical scavenger containing a hydroxyl group contains a phenolic radical scavenger.
<7> The above-mentioned one of <1> to <6>, wherein the radical scavenger containing a hydroxyl group contains a radical scavenger containing one hydroxyl group, an episulfide ring, and at least one of a sulfide bond and a disulfide bond. Episulfide composition.
<8> Any one of <1> to <7>, wherein the content of the radical scavenger containing a hydroxyl group is 10 mol ppm or more with respect to the content of the episulfide compound containing the episulfide ring and not containing a hydroxyl group. The episulfide composition according to.
<9> The episulfide composition according to any one of <1> to <8>, wherein the content of the episulfide compound containing the episulfide ring and not containing the hydroxyl group is 90% by mass or more with respect to the total amount of the episulfide composition. Stuff.
<10> The episulfide composition according to any one of <1> to <9>, which further contains a thiol compound.
<11> The episulfide composition according to any one of <1> to <10>, which further contains a polymerization catalyst.
<12> The episulfide composition according to any one of <1> to <11> used for producing an optical material.
<13> A cured product of the episulfide composition according to any one of <1> to <12>.
<14> An optical material containing the cured product according to <13>.

According to the present disclosure, an episulfide composition having excellent controllability of the polymerization rate of the episulfide compound and capable of suppressing deterioration of the characteristics of the resin obtained by the polymerization of the episulfide compound, a cured product of the episulfide composition, and the curing thereof. Optical materials, including objects, are provided.

In the present disclosure, the numerical range represented by using "~" means a range including the numerical values before and after "~" as the lower limit value and the upper limit value.
In the present disclosure, the amount of each component in the composition is the total amount of the plurality of substances present in the composition unless otherwise specified, when a plurality of substances corresponding to each component are present in the composition. means.
In the numerical range described stepwise in the present disclosure, the upper limit value or the lower limit value described in one numerical range may be replaced with the upper limit value or the lower limit value of another numerical range described stepwise. .. Further, in the numerical range described in the present disclosure, the upper limit value or the lower limit value of the numerical range may be replaced with the value shown in the examples.

[Episulfide composition]
The episulfide composition of the present disclosure includes an episulfide compound containing an episulfide ring and not containing a hydroxyl group (hereinafter, also referred to as a "specific episulfide compound") and a radical scavenger containing a hydroxyl group (hereinafter, also referred to as a "specific radical scavenger"). , Contain.

The episulfide composition of the present disclosure is excellent in controllability of the polymerization rate of a specific episulfide compound (hereinafter, also referred to as “polymerization rate controllability”). Further, according to the episulfide composition of the present disclosure, deterioration of the characteristics of the resin obtained by the polymerization of the specific episulfide compound can be suppressed.

In the present disclosure, the concept of the term "polymerization rate of a specific episulfide compound" includes not only the polymerization rate when the specific episulfide compound is polymerized alone, but also the specific episulfide compound and other monomers (for example, a thiol compound described later). The same applies hereinafter), and the polymerization rate when copolymerizing with) is also included.
Further, in the present disclosure, the concept of the term "polymerization of a specific episulfide compound" includes not only homopolymerization of a specific episulfide compound but also copolymerization of a specific episulfide compound with another monomer.

The effect of excellent controllability of the polymerization rate of the specific episulfide compound is an effect exhibited by the radical scavenging function of the specific radical scavenger.
In particular, the specific radical scavenger has excellent solubility in a specific episulfide compound. Therefore, the episulfide composition of the present disclosure can contain a larger amount of the radical scavenger as compared with the case where only the radical scavenger containing no hydroxyl group is used. Therefore, the episulfide composition of the present disclosure is excellent in polymerization rate controllability as compared with the case where only a radical scavenger containing no hydroxyl group is used.
Further, the specific radical scavenger is obtained by polymerization of a specific episulfide compound as compared with a radical scavenger containing no hydroxyl group (for example, a radical scavenger containing an N-oxyl group (for example, TEMPO in a comparative example described later)). There is little effect on the characteristics of the resin. Therefore, according to the episulfide composition of the present disclosure, deterioration of the characteristics of the resin obtained by the polymerization of the specific episulfide compound can be suppressed as compared with the case where only the radical scavenger containing no hydroxyl group is used.

Hereinafter, each component that can be contained in the episulfide composition of the present disclosure will be described.

<Specific episulfide compound>
The episulfide composition of the present disclosure contains a specific episulfide compound.
The specific episulfide compound is a compound containing one or more episulfide rings and not containing a hydroxyl group.
The specific episulfide compound contained in the episulfide composition of the present disclosure may be only one kind or two or more kinds.

The specific episulfide compound preferably contains a compound containing an episulfide ring and at least one of a sulfide bond and a disulfide bond (hereinafter, also referred to as “Compound E1”).

In the present disclosure, the term "disulfide bond" means a bond represented by "-SS-".
In the present disclosure, the term "sulfide bond" is used in the bond represented by "-S-" (provided that it is contained in the bond represented by "-S-" contained in the episulfide ring and the disulfide bond. (Excluding the bond represented by -S- ").
Supplementally, in the present disclosure, the episulfide ring and the disulfide bond are treated as an integral structure, respectively, and the bond represented by "-S-" contained in the episulfide ring and the "-S-" contained in the disulfide bond are contained. The bond represented by is not referred to as a "sulfide bond".

The molecular weight of the specific episulfide compound (for example, compound E1) is preferably 1000 or less, more preferably 800 or less, still more preferably 500 or less, still more preferably 300 or less.
The lower limit of the molecular weight of the episulfide compound is, for example, 100, preferably 130, and even more preferably 150.

The number of episulfide rings in the specific episulfide compound (for example, compound E1) is preferably two or more, more preferably two to four, and even more preferably two.

The specific episulfide compound preferably contains a compound represented by the following formula (1).
The compound represented by the following formula (1) is a preferred embodiment of compound E1.
The proportion of the compound represented by the formula (1) in the total amount of the specific episulfide compound is preferably 50% by mass to 100% by mass, more preferably 60% by mass to 100% by mass, and further preferably. It is 80% by mass to 100% by mass.

In the formula (1), R ^{1 to} R ⁵ are monovalent hydrocarbon groups that may be independently substituted with a hydrogen atom or a substituent other than a hydroxyl group, and m is 0 to 3. It is an integer, and n is an integer of 2 to 4.
When n is 2, L is an n-valent linking group, sulfide bond, or disulfide bond containing at least one of a sulfide bond and a disulfide bond and a hydrocarbon group and not containing a hydroxyl group.
When n is 3 or 4, L is an n-valent linking group containing at least one of a sulfide bond and a disulfide bond and a hydrocarbon group and containing no hydroxyl group.
Each of a plurality of R ^{1 to} R ⁵ and m may be the same or different.

In the formula (1), R ^{1 to} R ⁵ are monovalent hydrocarbon groups that may be independently substituted with a hydrogen atom or a substituent other than a hydroxyl group.
Examples of the substituent in the monovalent hydrocarbon group which may be substituted with a substituent other than the hydroxyl group include a halogen atom, a thiol group (that is, a mercapto group), an alkoxy group, an alkylthio group and the like.
The carbon number of the monovalent hydrocarbon group which may be substituted by a substituent other than the hydroxyl group is preferably 1 to 10 as the total carbon number including the carbon number of the substituent when it has a substituent. , More preferably 1 to 6, still more preferably 1 to 3, still more preferably 1 or 2, and even more preferably 1.
As the "monovalent hydrocarbon group which may be substituted with a substituent other than the hydroxyl group" represented by each of ^{R 1 to} R ^{5, preferably an alkyl group having 1 to 6 carbon atoms (that is, an unsubstituted alkyl group)} Group), more preferably an alkyl group having 1 to 3 carbon atoms, still more preferably a methyl group or an ethyl group, still more preferably a methyl group.
In the formula (1), it is particularly preferable that each of ^{R 1 to} R ^{5 is a hydrogen atom.}

In equation (1), m is an integer from 0 to 3.
M in the formula (1) is preferably an integer of 0 to 2, more preferably 0 or 1, and even more preferably 1.

In equation (1), n is an integer of 2-4.
N in the formula (1) is preferably 2.

In the formula (1), when n is 2, L is an n-valent (that is, divalent) linking group containing at least one of a sulfide bond and a disulfide bond and a hydrocarbon group and not containing a hydroxyl group, a sulfide bond. , Or a disulfide bond.

In the formula (1), when n is 3 or 4, L is an n-valent (that is, trivalent or tetravalent) n-valent (that is, trivalent or tetravalent) containing at least one of a sulfide bond and a disulfide bond and a hydrocarbon group and not containing a hydroxyl group. It is a linking group.

The hydrocarbon group in the n-valent linking group containing at least one of a sulfide bond and a disulfide bond and a hydrocarbon group and not containing a hydroxyl group may be a chain aliphatic group or a cyclic aliphatic group. , It may be an aromatic group, or it may be a group in which two or more of these are combined.
Further, the n-valent linking group may contain only one hydrocarbon group or two or more hydrocarbon groups.
Further, the n-valent linking group may contain at least one of a sulfide bond and a disulfide bond, or may contain two or more.
Further, the n-valent linking group may contain one or more sulfur-containing heterocyclic structures.

The number of carbon atoms (that is, the number of carbon atoms) in the n-valent linking group is preferably 1 to 30, more preferably 1 to 20, and even more preferably 1 to 10.
The number of sulfur (that is, the number of sulfur atoms) in the n-valent linking group is preferably 1 to 30, more preferably 1 to 20, and even more preferably 1 to 10.

Hereinafter, specific examples of n-valent linking groups containing at least one of a sulfide bond and a disulfide bond and a hydrocarbon group and not containing a hydroxyl group will be shown.
However, the n-valent linking group is not limited to the following specific examples.

First, specific examples of n-valent linking groups containing a sulfide bond and not containing a disulfide bond and a hydroxyl group are shown below. In the following specific example, * represents a bonding position.

Specific examples of an n-valent linking group containing at least one of a sulfide bond and a disulfide bond and a hydrocarbon group and not containing a hydroxyl group include the above-mentioned "n-valent n-valent group containing a sulfide bond and not containing a disulfide bond and a hydroxyl group". In each of the specific examples of "linking group", there is also a linking group in which at least one sulfide bond (-S-) is replaced with a disulfide bond (-S-S-).

The molecular weight of the compound represented by the formula (1) is preferably 1000 or less, more preferably 800 or less, still more preferably 500 or less, still more preferably 300 or less.
The lower limit of the molecular weight of the compound represented by the formula (1) is, for example, 60, preferably 100, and more preferably 130.

A preferred embodiment of the compound represented by the formula (1) is an embodiment in which n is 2 and L is a sulfide bond (-S-) or a disulfide bond (-S-S-) in the formula (1). ..

Among the compounds represented by the formula (1), the preferable compound is a compound in the formula (1) in which n is 2 and L is a disulfide bond (−S—S—) (hereinafter, “Compound (1A)). ”).
As a specific example of this embodiment, for example,
Bis (2,3-epithiopropyl) disulfide (hereinafter also referred to as "ETDS"),
Bis (1,2-epithioethyl) disulfide,
Bis (3,4-epiothiobutyl) disulfide,
Bis (4,5-epithiopentyl) disulfide,
Etc.,
Particularly preferred is bis (2,3-epithiopropyl) disulfide (ETDS).

Among the compounds represented by the formula (1), the preferable compound is a compound in the formula (1) in which n is 2 and L is a sulfide bond (-S-) (hereinafter, also referred to as "compound (1B)"). ) Can also be mentioned.
As a specific example of this embodiment, for example,
Bis (2,3-epithiopropyl) sulfide,
Bis (1,2-epithioethyl) sulfide,
Bis (3,4-epithiobutyl) sulfide,
Bis (4,5-epithiopentyl) sulfide,
Etc.,
Particularly preferred is bis (2,3-epithiopropyl) sulfide.

It is particularly preferable that the episulfide compound in the composition according to one aspect of the present disclosure contains at least one of compound (1A) and compound (1B).
In this case, the total ratio of the compound (1A) and the compound (1B) to the total amount of the episulfide compound contained in the composition according to one aspect of the present disclosure is preferably 50% by mass to 100% by mass. It is more preferably 60% by mass to 100% by mass, and further preferably 80% by mass to 100% by mass.

Specific examples of the specific episulfide compound (for example, the compound represented by the formula (1)) include the following specific examples in addition to the specific examples of the compound (1A) and the compound (1B) described above.
However, the specific episulfide compound is not limited to the following specific examples.

As an episulfide compound containing two or more episulfide rings and containing a chain aliphatic structure,
Bis (2,3-epithiopropylthio) methane,
1,2-bis (2,3-epithiopropylthio) ethane,
And so on.

As an episulfide compound containing two or more episulfide rings and containing a cyclic aliphatic structure or a sulfur-containing heterocyclic structure.
1,3-Bis (2,3-Epithiopropylthio) Cyclohexane,
1,4-Bis (2,3-Epithiopropylthio) Cyclohexane,
And so on.

As an episulfide compound containing two or more episulfide rings and containing an aromatic ring structure,
1,2-bis (2,3-epithiopropylthio) benzene,
1,3-Bis (2,3-Epithiopropylthio) Benzene,
And so on.

Examples of the specific episulfide compound include compounds in which at least one sulfide bond (-S-) is replaced with a disulfide bond (-S-S-) in each of the above-mentioned specific examples.

Examples of the specific episulfide compound include ethylene sulfide, propylene sulfide, 3-mercaptopropylene sulfide, 4-mercaptobutene sulfide, and the like as compounds containing only one episulfide ring.

For the specific episulfide compound, paragraphs 0014 to 0023 and 0043 to 0065 of JP-A-2002-194083 may be referred to.

The content of the specific episulfide compound is preferably 50% by mass or more, more preferably 60% by mass or more, still more preferably 80% by mass or more, still more preferably 90% by mass, based on the total amount of the episulfide composition. % Or more.
The upper limit of the content of the specific episulfide compound with respect to the total amount of the episulfide composition is appropriately selected according to the content of other components. Examples of the upper limit of the content of the specific episulfide compound with respect to the total amount of the episulfide composition include 99% by mass, 98% by mass, 95% by mass and the like.

<Specific radical scavenger>
The episulfide composition of the present disclosure contains a specific radical scavenger.
The specific radical scavenger is a radical scavenger containing a hydroxyl group.
As described above, the specific radical scavenger having a hydroxyl group has not only a function of capturing radicals but also a function of ensuring solubility in a specific episulfide compound.
The specific radical scavenger contained in the episulfide composition of the present disclosure may be only one kind or two or more kinds.

The molecular weight of the specific radical scavenger is not particularly limited, but is preferably 1000 or less, and more preferably 500 or less.
The lower limit of the molecular weight of the specific radical scavenger is, for example, 94.

The specific radical scavenger is not particularly limited as long as it is a compound containing a hydroxyl group and having a radical scavenging function.
From the viewpoint of further improving the solubility in the specific episulfide compound, the specific radical scavenger preferably contains a ring structure, and more preferably contains at least one of a benzene ring and an episulfide ring.

From the viewpoint that the effects of the episulfide composition of the present disclosure are more effectively exerted, the specific radical scavenger preferably contains at least one of the phenolic radical scavenger and the episulfide radical scavenger described below.
In this case, the total ratio of the phenol-based radical scavenger and the episulfide-based radical scavenger to the specific radical scavenger is preferably 50% by mass to 100% by mass, and more preferably 60% by mass to 100% by mass. It is more preferably 80% by mass to 100% by mass.

The specific radical scavenger preferably contains a phenolic radical scavenger. Phenolic radical scavengers have high radical scavenging ability because they are highly soluble in specific episulfide compounds.
Examples of the phenolic antioxidant include phenol, hydroquinone, 2-methoxyhydroquinone, 2,6-di-tert-butyl-p-cresol (hereinafter, also referred to as "BHT") and the like.

The specific radical scavenger preferably contains a radical scavenger containing one hydroxyl group, an episulfide ring, and at least one of a sulfide bond and a disulfide bond (hereinafter, also referred to as "episulfide-based radical scavenger"). Episulfide-based radical scavengers have high radical scavenging ability because they are highly soluble in specific episulfide compounds.
As the episulfide-based radical scavenger, a compound in which one hydrogen atom in a specific episulfide compound (for example, a compound represented by the formula (1)) is replaced with a hydroxyl group can be used.

The number of episulfide rings contained in the specific radical scavenger may be only one or two or more.
When the specific radical scavenger contains sulfide bonds, the number of sulfide bonds contained in the specific radical scavenger may be only one or two or more.
When the specific radical scavenger contains disulfide bonds, the number of disulfide bonds contained in the specific radical scavenger may be only one or two or more.

As an episulfide-based radical scavenger, it is preferably a compound represented by the following formula (C1).

In the formula (C1), R ^{1c to} R ^5c are monovalent hydrocarbon groups that may be independently substituted with a hydrogen atom or a substituent other than a hydroxyl group, and mc is 0 to 3. is an integer, nc is an integer from 2 to 4, L ^c is at least one sulfide bond and disulfide bonds, a n-valent linking group containing a hydrocarbon group and one hydroxyl group.
Each of a plurality of R ^{1c to} R ^5c and mc may be the same or different.

In the formula (C1), each of R ^{1c to} R ^5c , mc, and nc ^{is synonymous with each of R 1 to} R ⁵ , m, and n in the formula (1), and the preferred embodiment is also the same. ..
In the formula (C1), L ^c contains at least one of a sulfide bond and a disulfide bond and a hydrocarbon group and contains a hydroxyl group, which is represented by L in the formula (1), except that it contains one hydroxyl group. It is synonymous with "n-valent linking group not included".

The episulfide-based radical scavenger is more preferably the following compound (C1-1) or the following compound (C1-2), and further preferably the following compound (C1-1).

In the episulfide composition of the present disclosure, the content of the specific radical scavenger with respect to the content of the specific episulfide compound is not particularly limited, and depends on the degree of the target polymerization rate controllability (that is, the degree of controlling the polymerization rate). Is adjusted as appropriate.
From the viewpoint of obtaining better polymerization rate controllability, the content of the specific radical scavenger with respect to the content of the specific episulfide compound is preferably 10 molppm or more, more preferably 100 molppm or more, still more preferably. It is 300 mol ppm or more.
The upper limit of the content of the specific radical scavenger with respect to the content of the specific episulfide compound is not particularly limited, but is preferably 10,000 mol ppm or less, more preferably 5,000, from the viewpoint of maintaining the physical characteristics of the obtained resin better. It is mol ppm or less, more preferably 1000 mol ppm or less.

<Thiol compound>
The episulfide composition of the present disclosure preferably further contains a thiol compound.
When the episulfide composition of the present disclosure further contains a thiol compound, a resin (that is, a cured product) can be obtained by polymerizing the specific episulfide compound and the thiol compound in the episulfide composition. The obtained resin may be excellent in heat resistance, mechanical properties, optical properties, and the like.
When the episulfide composition of the present disclosure contains a thiol compound, the thiol compound contained may be only one kind or two or more kinds.

Examples of the thiol compound include aliphatic thiols and aromatic thiols.

As an aliphatic thiol,
Pentaerythritol tetrakis (2-mercaptothioglycolate),
Pentaerythritol tetrakis (3-mercaptopropionate),
Trimethylol Propantris (2-mercaptothioglycolate),
Trimethylol propanthris (3-mercaptopropionate),
4-Mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane,
2,5-Dimercaptomethyl-1,4-dithiane,
2,5-bis [(2-mercaptoethyl) thiomethyl] -1,4-dithiane,
1,3-Cyclohexanedithiol,
1,4-Cyclohexanedithiol,
Bis (mercaptomethyl) sulfide,
Bis (mercaptomethyl) disulfide,
Bis (mercaptoethyl) sulfide,
Bis (mercaptoethyl) disulfide,
4,8-Dimercaptomethyl-1,11-Dimercapto-3,6,9-Trithiandecan,
4,7-Dimercaptomethyl-1,11-Dimercapto-3,6,9-Trithiandecan,
5,7-Dimercaptomethyl-1,11-Dimercapto-3,6,9-Trichiaundecane, and
At least one selected from the group consisting of tetrakis (mercaptomethylthio) propane is preferred.
However, the aliphatic thiol is not limited to these specific examples.

As an aromatic thiol,
Benzyl thiol,
Xylylene thiol,
1,3-bis (mercaptoethyl) benzene,
1,4-Bis (mercaptoethyl) benzene 2,5-toluenedithiol,
3,4-Toluenedithiol,
Thiophenol,
1,2-Dimercaptobenzene,
1,3-Dimercaptobenzene,
1,4-Dimercaptobenzene, and
At least one selected from the group consisting of 1,2-bis (mercaptomethyl) benzene is preferred.
However, aromatic thiols are not limited to these specific examples.

As the thiol compound, a compound having two or more thiol groups (that is, a mercapto group) (hereinafter, also referred to as “polythiol compound”) is preferable.

When the episulfide composition of the present disclosure contains a thiol compound, the thiol compound preferably contains an aliphatic polythiol (that is, an aliphatic thiol which is a polythiol compound).
In this case, the proportion of the aliphatic polythiol in the total amount of the thiol compound is preferably 50% by mass, more preferably 60% by mass or more, and further preferably 80% by mass or more.
There is no particular limitation on the upper limit of the proportion of the aliphatic thiol. The proportion of the aliphatic thiol may be 100% by mass, less than 100% by mass, 99% by mass or less, or 95% by mass or less.

Thiol compounds
4-Mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane,
4,8-Dimercaptomethyl-1,11-Dimercapto-3,6,9-Trithiandecan,
Consists of 4,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane and 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane It is more preferable to include at least one selected from the group (hereinafter, also referred to as "polythiol A").
In this case, the proportion of polythiol A in the total amount of the thiol compound is preferably 50% by mass, more preferably 60% by mass or more, and further preferably 80% by mass or more.
There is no particular limitation on the upper limit of the proportion of polythiol A. The ratio of the polythiol A may be 100% by mass, less than 100% by mass, 99% by mass or less, or 95% by mass or less.

Thiol compounds
4,8-Dimercaptomethyl-1,11-Dimercapto-3,6,9-Trithiandecan,
Consists of 4,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane and 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane It is more preferable to include at least one selected from the group (hereinafter, also referred to as "polythiol A1").
In this case, the proportion of polythiol A1 in the total amount of the thiol compound is preferably 50% by mass, more preferably 60% by mass or more, and further preferably 80% by mass or more.
There is no particular limitation on the upper limit of the proportion of polythiol A1. The ratio of the polythiol A1 may be 100% by mass, less than 100% by mass, 99% by mass or less, or 95% by mass or less.

When the episulfide composition of the present disclosure contains a thiol compound, the content of the thiol compound is preferably 1% by mass to 50% by mass, more preferably 2% by mass to 30% by mass, based on the total amount of the specific episulfide compound. It is more preferably 3% by mass to 20% by mass, and further preferably 5% by mass to 15% by mass.

For thiol compounds, paragraph 0039 of WO 2018/079829 may be referred to.

<Polymerization catalyst>
The episulfide composition of the present disclosure preferably further contains a polymerization catalyst.
In this case, the polymerization catalyst contained in the episulfide composition may be only one kind or two or more kinds.

Examples of the polymerization catalyst include tertiary amine compounds, phosphine compounds, Lewis acids, radical polymerization catalysts, cationic polymerization catalysts and the like.
As the polymerization catalyst, for example, the description in paragraphs 0029 to 0033 of JP-A-2002-194083 can be referred to.

The polymerization catalyst is preferably a tertiary amine compound or a phosphine compound.
As a tertiary amine compound,
Triethylamine,
Tri-n-butylamine,
Tri-n-hexylamine,
N, N-diisopropylethylamine,
Triethylenediamine,
Triphenylamine,
N, N-dimethylethanolamine,
N, N-diethylethanolamine,
N, N-dibutylethanolamine,
Triethanolamine,
N-Ethyl Diethanolamine,
N, N-dimethylbenzylamine,
N, N-diethylbenzylamine,
Tribenzylamine,
N-Methyldibenzylamine,
N, N-dimethylcyclohexylamine,
N, N-dicyclohexylmethylamine,
N, N-diethylcyclohexylamine,
N, N-dicyclohexylethylamine,
N, N-dimethylbutylamine,
N, N-dicyclohexylbutylamine,
N-methylmorpholine,
N-Isopropyl morpholine,
Pyridine,
Quinoline,
N, N-dimethylaniline,
N, N-diethylaniline,
α-picoline,
β-picoline,
γ-picoline,
2,2'-bipyridyl,
1,4-Dimethylpiperazine,
Tetramethylethylenediamine,
Hexamethylenetetramine,
1,8-Diazabicyclo (5,4,0) -7-Undesen,
2,4,6-tris (N, N-dimethylaminomethyl) phenol, and the like can be mentioned.

As a phosphine compound,
Trimethylphosphine,
Triethylphosphine,
Tri-n-propylphosphine,
Triisopropylphosphine,
Tri n-butylphosphine,
Triphenylphosphine,
Tribenzylphosphine,
1,2-bis (diphenylphosphino) ethane,
1,2-bis (dimethylphosphino) ethane,
And so on.

When the episulfide composition of the present disclosure contains a polymerization catalyst, the content of the polymerization catalyst is preferably 0.01% by mass to 5% by mass, more preferably 0.01% by mass, based on the total amount of the episulfide composition. It is ~ 2% by mass, more preferably 0.03% by mass ~ 1% by mass.

<Other ingredients>
The episulfide composition of the present disclosure may contain other components other than those described above.
Other components include epoxy compounds, alcohol compounds (eg polyol compounds), mercapto organic acids, resins (eg acrylic resins, olefin resins, etc.), cross-linking agents, light stabilizers, UV absorbers, antioxidants, anti-coloring agents. Examples include agents, dyes, fillers, internal mold release agents and the like.
As the other components, known components can be used.
For other components, for example, JP-A-2002-194083 can be referred to as appropriate.

The use of the episulfide composition of the present disclosure is not particularly limited.
Since the episulfide composition of the present disclosure can produce a cured product of an episulfide compound capable of having a high refractive index, it is suitably used for, for example, in the production of an optical material. The optical material will be described later.

[Cured product]
The cured product of the present disclosure is a cured product of the episulfide composition of the present disclosure.
The cured product of the present disclosure is the episulfide composition of the present disclosure, for example, by polymerizing a monomer in the episulfide composition of the present disclosure (for example, a specific episulfide compound alone, a combination of an episulfide compound and another monomer, etc.). Is obtained by curing. The cured product of the present disclosure in this case contains a resin obtained by polymerizing the monomers in the episulfide composition of the present disclosure.

The method of polymerizing the monomers in the episulfide composition of the present disclosure (that is, the method of producing the cured product of the present disclosure) is not particularly limited.
Examples of the method for polymerizing the monomers in the episulfide composition of the present disclosure include cast polymerization.
In the cast polymerization, first, the episulfide composition of the present disclosure is injected between molding molds held by a gasket, tape or the like. At this time, if necessary, defoaming treatment, filtration treatment and the like may be performed.
Next, by polymerizing the monomers in the composition injected between the molding molds, the composition is cured between the molding molds to obtain a cured product. Then, the cured product is removed from the molding mold to obtain a cured product.
The polymerization of the above-mentioned monomers may be carried out by heating the episulfide composition of the present disclosure. This heating can be performed, for example, by using a heating device provided with a mechanism for heating the object to be heated in an oven, water, or the like.

The polymerization conditions (for example, polymerization temperature, polymerization time, etc.) for polymerizing the monomers in the episulfide composition of the present disclosure include the composition of the composition, the type and amount of the monomer in the composition, and the polymerization catalyst in the composition. It is set as appropriate in consideration of the type and amount used, the shape of the mold, and the like.
Examples of the polymerization temperature include −50 ° C. to 150 ° C., 10 ° C. to 150 ° C., and the like.
Examples of the polymerization time include 1 hour to 200 hours, 1 hour to 80 hours, and the like.

The cured product of the present disclosure may be obtained by subjecting a treatment such as annealing after polymerization of the monomer.
Examples of the annealing temperature include 50 ° C. to 150 ° C., 90 ° C. to 140 ° C., 100 ° C. to 130 ° C., and the like.

Since the cured product of the present disclosure is a cured product of the episulfide composition, it can have a high refractive index.
The refractive index (nd) of the cured product of the present disclosure is preferably 1.71 or more, more preferably 1.72 or more, and further preferably 1.73 or more.

Further, by changing the molding mold at the time of casting polymerization, cured products having various shapes can be obtained.
Therefore, the cured product of the present disclosure can be suitably used as, for example, a material for an optical material such as a spectacle lens, a camera lens, or a light emitting diode (LED); a material for a transparent resin member, and the like.

[Optical material]
The optical materials of the present disclosure include the cured products of the present disclosure.
The optical material of the present disclosure may consist of the cured product of the present disclosure, or may include the cured product of the present disclosure and other elements.
Other elements include other members, a coating layer provided on the cured product of the present disclosure, and the like.

The optical material of the present disclosure may have a high refractive index because it contains a cured product of the episulfide composition.
The refractive index (nd) of the optical material of the present disclosure is preferably 1.71 or more, more preferably 1.72 or more, and further preferably 1.73 or more.

Examples of the optical material of the present disclosure include spectacle lenses, camera lenses, polarized lenses, light emitting diodes (LEDs), and the like.

-Glasses lens-
Hereinafter, a spectacle lens will be described as an example of the optical material of the present disclosure.
The spectacle lens includes a cured product of the present disclosure molded into a desired lens shape.
The spectacle lens preferably further comprises a coating layer provided on one or both sides of the cured product.

Specific examples of the coating layer include a primer layer, a hard coat layer, an antireflection layer, an antifogging coat layer, an antifouling layer, and a water repellent layer. Each of these coating layers can be used alone, or a plurality of coating layers can be used in multiple layers.
When coating layers are applied to both sides of the cured product, the same coating layer may be applied to each surface, or different coating layers may be applied to each surface.

The components of the coating layer can be appropriately selected depending on the intended purpose.
Examples of the components of the coating layer include resins (for example, urethane resin, epoxy resin, polyester resin, melamine resin, polyvinyl acetal resin, etc.), infrared absorbers, light stabilizers, antioxidants, photochromic compounds, dyes, etc. Examples include pigments and antistatic agents.

Regarding the spectacle lens and the coating layer, for example, the description of publicly known documents such as JP-A-2002-194883 and International Publication No. 2017/0477445 can be referred to as appropriate.

Hereinafter, examples of the present disclosure will be shown, but the present disclosure is not limited to the following examples.

[Example 1]
<Preparation of Composition A>
Bis (2,3-epithiopropyl) disulfide (ETDS) (100 g; 0.46 mol) with a purity of 96.8 mass% as a specific episulfide compound and phenol (14.3 mg; 0.000152 mol) as a radical scavenger. Was added and mixed to completely dissolve. The obtained solution was filtered through a Teflon filter having a pore size of 3 μm to obtain Composition A as an episulfide composition.

<Preparation of Composition B>
In the above composition A (60 g),
N, N-dimethylcyclohexylamine (0.012 g) [polymerization catalyst] and
N, N-dicyclohexylmethylamine (0.060 g) [polymerization catalyst] and
4,8-Dimercaptomethyl-1,11-Dimercapto-3,6,9-Trithiandecan, 4,7-Dimercaptomethyl-1,11-Dimercapto-3,6,9-Trithiaundecane, and 5 , 7-Dimercaptomethyl-1,11-Dimercapto-3,6,9-Trithiaundecane as a main component (specifically, 80% by mass based on the total mixture S1) Mixture S1 (6.0 g) [ Mixture of thiol compounds] and
Was added, and the mixture was stirred at 20 ° C. for 15 minutes to obtain Composition B as an episulfide composition.

<Evaluation of polymerization rate controllability>
The above composition B (10 g) was placed in a glass container, and a thermometer with a recorder was inserted into the composition B in the container. In this state, the container was placed in an oven and kept warm at an oven temperature of 30 ° C. for 15 hours to polymerize the monomers (EDTS and mixture S1) in the composition B.
During the above polymerization (ie, 15 hours), the internal temperature of composition B was recorded.
Based on the recording result of the internal temperature, the time (h) from the start of the polymerization until the internal temperature reaches the maximum reached temperature was determined. Here, the internal temperature of the composition B rises when the polymerization is started and then falls, so that the peak top temperature of the internal temperature (that is, the temperature at which the temperature starts to fall) at the polymerization time of 30 hours is defined as the maximum temperature reached. did.
The polymerization rate controllability was evaluated based on the time (h) from the start of polymerization until the internal temperature reached the maximum temperature.
The results are shown in Table 1.
In this evaluation, the longer the time (h) from the start of polymerization until the internal temperature reaches the maximum temperature, the better the polymerization rate controllability.

<Making a flat lens>
A flat lens was produced as a cured product of the composition B as follows.
Composition B was injected between a pair of tape-fixed glass molds. Next, a pair of glass molds infused with composition B are placed in an oven and kept warm at an oven temperature of 30 ° C. for 15 hours, and then gradually so that the oven temperature reaches 80 ° C. over 10 hours. It was warmed. Then, the temperature was kept in the oven at 80 ° C. for 2 hours. Through the above process, the monomers (EDTS and the mixture S1) in the composition B were polymerized to form a resin molded product (that is, a cured product of the composition B) between the pair of glass molds.
After keeping the heat for 2 hours, the inside of the oven was cooled, and after cooling, the pair of glass molds were taken out from the oven, and then the resin molded body was removed from the pair of glass molds to obtain a resin molded body. The obtained resin molded body was annealed at 120 ° C. for 3 hours to obtain a circular flat lens having a thickness of 9 mm and a diameter of 75 mm.

<Measurement of yellow index value (YI value) of flat lens>
The yellow index value (YI value) of the flat lens obtained above was measured using a color difference meter "CR-400" manufactured by Minolta Co., Ltd. as one of the indexes of the characteristics of the resin.
The results are shown in Table 1.
Y. I. The smaller the value, the less yellowish the flat lens is (that is, the better the resin characteristics).

<Measurement of devitrification of flat lens>
Light from a light source (Luminar Ace LA-150A manufactured by Hayashi Repic Co., Ltd.) was transmitted through the flat lens obtained above. The image of the light transmitted through the flat lens was captured in an image processing device (manufactured by Ube Information Systems Inc.), and the captured image was subjected to shading processing. The degree of shading of the processed image was quantified for each pixel, the average value of the degree of shading of each pixel was obtained, and the devitrification of the flat lens was obtained.
With respect to the devitrification of the obtained flat lens, a relative value was calculated when the devitrification of the flat lens in Comparative Example 1 was 100, and the obtained relative value was defined as "devitrification (relative value)". ..
The results are shown in Table 1.
The smaller the devitrification, the less the transparency of the resin (here, the flat lens) is impaired (that is, the better the characteristics of the resin).

[Examples 2 to 5, Comparative Example 2]
The same operation as in Example 1 was carried out except that the type and amount of the radical scavenger (amount with respect to the specific episulfide compound) were changed as shown in Table 1.
The results are shown in Table 1.

-Explanation of abbreviations in Table 1-
TEMPO: 2,2,6,6-tetramethylpiperidine 1-oxyl (N-oxyl radical scavenger). A comparative radical scavenger that does not contain hydroxyl groups.
・ BHT: 2,6-di-tert-butyl-p-cresol (phenolic radical scavenger)
(C1-1) ... The above-mentioned compound (C1-1) which is a specific example of an episulfide-based radical scavenger (that is, a radical scavenger containing one hydroxyl group, an episulfide ring, and at least one of a sulfide bond and a disulfide bond). ..

[Comparative Example 3]
The same operation as in Example 1 was carried out except that the type of the radical scavenger was changed to TEMPO as shown in Table 1.
The results are shown in Table 1.
As shown in Table 1, in Comparative Example 3, 330 mol ppm of TEMPO could not be dissolved in the specific episulfide compound, and the polymerization rate controllability, Y. I. The value and devitrification could not be evaluated.

[Comparative Example 1]
The same operation as in Example 1 was carried out except that the radical scavenger was not used (specifically, EDTS alone was used instead of the composition A).
The results are shown in Table 1.

As shown in Table 1, an episulfide composition containing a specific episulfide compound (that is, an episulfide compound containing an episulfide ring and not containing a hydroxyl group) and a specific radical scavenger (that is, a radical scavenger containing a hydroxyl group) (details). In Examples 1 to 5 using the composition A and the composition B), the controllability of the polymerization rate was excellent as compared with Comparative Example 1 (without the radical scavenger).
Further, as shown in Examples 1 to 5 and Comparative Example 1, in Examples 1 to 5, the properties of the resin are deteriorated due to the addition of the specific radical scavenger (specifically, the YI value and the loss). (Increase in transparency) was suppressed.
Compared to Examples 1 to 5, in Comparative Example 3, TEMPO, which is a comparative radical scavenger containing no hydroxyl group, could not dissolve an amount of 330 mol ppm in a specific episulfide compound.
Further, in Comparative Example 2 in which an amount of 33 mol ppm of TEMPO was used for the specific episulfide compound, although it was possible to dissolve in the specific episulfide compound, the polymerization rate was higher than that in Examples 1 to 5. It was inferior in controllability. Further, in Comparative Example 2, the characteristics of the resin were lowered as compared with Examples 1 to 5 (specifically, the YI value and the devitrification were increased).

Claims (14)

An episulfide composition containing an episulfide compound containing an episulfide ring and not containing a hydroxyl group, and a radical scavenger containing a hydroxyl group. The episulfide composition according to claim 1, wherein the episulfide compound containing an episulfide ring and not containing a hydroxyl group contains a compound containing an episulfide ring and at least one of a sulfide bond and a disulfide bond. The episulfide composition according to claim 1 or 2, wherein the episulfide compound containing an episulfide ring and not containing a hydroxyl group contains a compound represented by the following formula (1).

[In the formula (1), R ^{1 to} R ⁵ are monovalent hydrocarbon groups that may be independently substituted with a hydrogen atom or a substituent other than a hydroxyl group, and m is 0 to 3. And n is an integer of 2-4.
When n is 2, L is an n-valent linking group, sulfide bond, or disulfide bond containing at least one of a sulfide bond and a disulfide bond and a hydrocarbon group and not containing a hydroxyl group.
When n is 3 or 4, L is an n-valent linking group containing at least one of a sulfide bond and a disulfide bond and a hydrocarbon group and containing no hydroxyl group.
Each of a plurality of R ^{1 to} R ⁵ and m may be the same or different. ] The episulfide composition according to claim 3, wherein in the formula (1), the n is 2 and the L is a disulfide bond. The episulfide composition according to any one of claims 1 to 4, wherein the radical scavenger containing a hydroxyl group further contains at least one of a benzene ring and an episulfide ring. The episulfide composition according to any one of claims 1 to 5, wherein the radical scavenger containing a hydroxyl group contains a phenolic radical scavenger. The episulfide composition according to any one of claims 1 to 6, wherein the radical scavenger containing a hydroxyl group contains a radical scavenger containing one hydroxyl group, an episulfide ring, and at least one of a sulfide bond and a disulfide bond. .. The invention according to any one of claims 1 to 7, wherein the content of the radical scavenger containing a hydroxyl group is 10 molppm or more with respect to the content of the episulfide compound containing the episulfide ring and not containing a hydroxyl group. Episulfide composition. The episulfide composition according to any one of claims 1 to 8, wherein the content of the episulfide compound containing an episulfide ring and not containing a hydroxyl group is 90% by mass or more with respect to the total amount of the episulfide composition. The episulfide composition according to any one of claims 1 to 9, further comprising a thiol compound. The episulfide composition according to any one of claims 1 to 10, further comprising a polymerization catalyst. The episulfide composition according to any one of claims 1 to 11, which is used for producing an optical material. The cured product of the episulfide composition according to any one of claims 1 to 12. An optical material containing the cured product according to claim 13.