Curable composition, cured product, optical article, lens, and glasses

Abstract

Provided is a curable composition comprising: a first bismuth compound containing bismuth and at least one of an acryloyl group and a methacryloyl group; and a first polymerizable compound containing at least one polymerizable group selected from the group consisting of an acryloyl group, a methacryloyl group, a vinyl group, and an allyl group, the boiling point of the first polymerizable compound at one atmospheric pressure being 90 DEG C or higher, and the content of a nitrile compound having a nitrile group being less than 10 mass%. Also provided are a cured product of the curable composition, an optical article and a lens comprising the cured product, and glasses comprising the lens.

Description

Technical Field

[0001] The present invention relates to a curable composition, a cured product, an optical article, a lens and glasses. Background Art

[0002] Directly irradiated X-rays and indirectly irradiated stray X-rays through reflection or scattering will affect the lens of the human eyeball and may induce cataracts. In order to solve this problem, it is desired to have optical articles such as lenses that can block these X-rays and transmit visible light. Lead glass is known as an optical material for forming such optical articles. Although lead glass has high X-ray blocking performance, it has a high specific gravity. Therefore, X-ray blocking goggles with lenses containing lead glass have a large mass and are difficult to use frequently. As another optical material, lead acrylate is also known. Although lead acrylate has a lower X-ray blocking performance than lead glass, it is lightweight. Therefore, lead acrylate is used in optical articles for blocking stray X-rays.

[0003] However, lead is a substance that is harmful to the environment, and optical materials that do not use lead are desired. As substitute elements for lead, for example, various metal elements such as bismuth, barium, antimony, tin, and tungsten can be selected as candidates. Among them, bismuth is an element that has been used as a gastrointestinal drug since ancient times, is harmless to the human body, has high X-ray blocking performance, and is suitable for replacing lead.

[0004] The cured product of the curable composition comprising a bismuth compound in which a phosphate having a (meth)acryloyl group is bonded to bismuth and a radical polymerizable monomer has high transparency and light weight, and is suitable as an optical material (see Patent Documents 1 and 2). In order to improve the mechanical properties of the cured product, the addition of a nitrile compound to the curable composition has been studied.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: International Publication No. 2022 / 014591

[0008] Patent Document 2: International Publication No. 2019 / 177084 Summary of the invention

[0009] Problem that the invention aims to solve

[0010] An object of the present invention is to provide a curable composition with reduced odor, a cured product with reduced odor, and an optical article, a lens, and glasses including the cured product.

[0011] Solutions for solving problems

[0012] Specific means for solving the above technical problems include the following implementation methods.

[0013] <1> A curable composition comprising:

[0014] a first bismuth compound containing bismuth and at least one of an acryloyl group and a methacryloyl group;

[0015] a first polymerizable compound containing at least one polymerizable group selected from the group consisting of an acryloyl group, a methacryloyl group, a vinyl group, and an allyl group, wherein the first polymerizable compound has a boiling point of 90° C. or higher at 1 atmosphere,

[0016] The content of the nitrile compound having a nitrile group is less than 10% by mass.

[0017] <2> The curable composition according to <1>, wherein the content of the first bismuth compound is 20% by mass or more and 90% by mass or less.

[0018] <3> The curable composition according to <1> or <2>, wherein the content of the first polymerizable compound is 10% by mass or more and 80% by mass or less.

[0019] <4> The curable composition according to any one of <1> to <3>, wherein the first polymerizable compound includes a monofunctional polymerizable compound having one polymerizable group.

[0020] <5> The curable composition according to <4>, wherein the monofunctional polymerizable compound has a boiling point of 100° C. to 300° C.

[0021] <6> The curable composition according to <4> or <5>, wherein the monofunctional polymerizable compound comprises a monofunctional (meth)acrylate represented by the following formula (I),

[0022]

[0023] In the aforementioned formula (I),

[0024] R 1 is a hydroxyl group, a linear or branched alkyl group having 1 to 10 carbon atoms, a linear or branched alkoxy group having 1 to 10 carbon atoms, a cycloalkyl group having 4 to 10 carbon atoms, a heterocycloalkyl group having 3 to 10 carbon atoms and 1 to 3 heteroatoms, an aryl group having 4 to 10 carbon atoms, or a heteroaryl group having 3 to 10 carbon atoms and 1 to 3 heteroatoms,

[0025] R 2 is a linear or branched alkylene group having 1 to 10 carbon atoms, or an alkyleneoxy group having 1 to 10 carbon atoms,

[0026] R3 is a hydrogen atom or a methyl group,

[0027] a is 0 or 1.

[0028] <7> The curable composition according to any one of <4> to <6>, wherein the monofunctional polymerizable compound comprises at least one (meth)acrylate selected from the group consisting of methoxyethyl acrylate, ethoxyethyl acrylate, methoxyethyl methacrylate, ethoxyethyl methacrylate, tetrahydrofurfuryl acrylate, and tetrahydrofurfuryl methacrylate.

[0029] <8> The curable composition according to any one of <1> to <7>, wherein the first polymerizable compound includes a polyfunctional polymerizable compound having two or more polymerizable groups.

[0030] <9> The curable composition according to <8>, wherein the polyfunctional polymerizable compound has a number average molecular weight of 90 or more and 2,000 or less as analyzed by gel permeation chromatography.

[0031] <10> The curable composition according to <8> or <9>, wherein the polyfunctional polymerizable compound comprises a bifunctional (meth)acrylate represented by the following formula (II),

[0032]

[0033] In the above formula (II),

[0034] R 4 is a linear or branched alkylene group having 1 to 10 carbon atoms, or a linear or branched alkyleneoxy group having 1 to 10 carbon atoms,

[0035] R 5 and R 6 are each independently a hydrogen atom or a methyl group,

[0036] n is a number of 1 or more and 50 or less.

[0037] <11> The curable composition according to any one of <8> to <10>, wherein the polyfunctional polymerizable compound comprises a bifunctional (meth)acrylate selected from the group consisting of polyethylene glycol dimethacrylate, polyethylene glycol diacrylate, polypropylene glycol dimethacrylate, polypropylene glycol diacrylate, polytetramethylene glycol dimethacrylate and polytetramethylene glycol diacrylate.

[0038] <12> A cured product comprising the curable composition according to any one of <1> to <11>.

[0039] <13> An optical article comprising the cured product according to <12>.

[0040] <14> A lens comprising the cured product according to <12>.

[0041] <15> A pair of glasses comprising the lens described in <14>.

[0042] Effects of the Invention

[0043] According to the present invention, there can be provided a curable composition with reduced odor, a cured product with reduced odor, and an optical article, a lens, and glasses including the cured product. DETAILED DESCRIPTION

[0044] Hereinafter, specific embodiments to which the present invention is applied will be described in detail.

[0045] In this specification, the term "(meth)acrylate" means both "acrylate" and "methacrylate", and the term "(meth)acryl" means both "acryl" and "methacryl". The same applies to terms such as "(meth)acrylic resin" and "(meth)acrylic acid".

[0046] 《Curing composition》

[0047] The curable composition of the present embodiment includes: a first bismuth compound and a first polymerizable compound. The first bismuth compound includes: bismuth, and at least one of an acryloyl group and a methacryloyl group. The first polymerizable compound has a boiling point of 90° C. or more at 1 atmosphere and has a polymerizable group. The polymerizable group includes at least one selected from the group consisting of an acryloyl group, a methacryloyl group, a vinyl group, and an allyl group. In the curable composition of the present embodiment, the content of the nitrile compound having a nitrile group is less than 10% by mass.

[0048] The first bismuth compound is light in weight and highly transparent, and is suitable as an X-ray blocking optical material. In addition, the first bismuth compound has high compatibility with other polymerizable compounds such as (meth)acrylate monomers or high dispersibility in other polymerizable compounds. Therefore, similar to general curable compositions such as (meth)acrylic resins, the first bismuth compound can be mixed with other polymerizable compounds. When nitrile compounds such as acrylonitrile are used as other polymerizable compounds, a cured product with high strength can be obtained.

[0049] However, the curable composition containing the first bismuth compound and its cured product sometimes have a unique odor. The inventors and others conducted in-depth research and found that the cause of the odor is derived from the unpolymerized nitrile compound remaining in the cured product. It is also found that polymerizable compounds with a lower boiling point at normal pressure are easily volatilized from the cured product, which may be the cause of the odor. The curable composition of the present embodiment contains a first polymerizable compound with a limited amount of nitrile compounds and a higher boiling point. Therefore, according to the curable composition of the present embodiment, a cured product with reduced odor can be obtained. When using a curable composition with reduced odor, the discomfort of the manufacturer or processor of the cured product and the user of the optical article containing the cured product is reduced, and the production efficiency can be further improved.

[0050] Hereinafter, each component used in the curable composition of this embodiment will be described.

[0051] <First Bismuth Compound>

[0052] Since the first bismuth compound contains bismuth, it can be used as a shielding material for radiation. Radiation includes electromagnetic radiation and particle radiation. Electromagnetic radiation includes X-rays and gamma rays. Particle radiation includes alpha rays, beta rays, neutron radiation and proton beams.

[0053] The first bismuth compound has excellent X-ray shielding performance and is therefore particularly suitable for use as an X-ray shielding material and a β-ray shielding material that can generate X-rays.

[0054] The first bismuth compound has high solubility in a radical polymerizable compound having at least one radical polymerizable group selected from the group consisting of a nitrile group, an acryloyl group, a methacryloyl group, a vinyl group, and an allyl group. Therefore, when the first bismuth compound is used, a curable composition containing a high concentration of bismuth and a cured product thereof can be obtained. The first bismuth compound has excellent solubility in a radical polymerizable compound compared to a bismuth subsalicylate monomer.

[0055] The first bismuth compound may be in any form as long as it contains bismuth and a (meth)acryloyl group. For example, bismuth and the (meth)acryloyl group may be bonded directly or via a bonding group. Examples of bonding groups include oxygen, sulfur, nitrogen, phosphoric acid, and the like. The first bismuth compound is preferably a bismuth bonded to a first phosphate ester having a (meth)acryloyl group. This first bismuth compound tends to have a higher compatibility with various polymerizable compounds. The bonding method of bismuth and the first phosphate ester is not particularly limited, and may be any of an ionic bond, a coordination bond, and a covalent bond. That is, the first bismuth compound may be a bismuth (Bi)-containing compound. 3+ Or Bi 5+ ) as a cation and the first phosphate ester as an anion, and can be either a phosphate compound or a complex.

[0056] The first bismuth compound may be a mono(meth)acrylate having one (meth)acryloyl group, a di(meth)acrylate having two (meth)acryloyl groups, a tri(meth)acrylate having three (meth)acryloyl groups, or a multifunctional (meth)acrylate having four or more (meth)acryloyl groups.

[0057] In the first bismuth compound, the first phosphate ester is represented by the following formula (2), for example.

[0058]

[0059] In the above formula (2), Q 1 is a hydrogen atom or a methyl group. 1 Preferred is methyl.

[0060] Q 2 It is a hydrogen atom, a linear or branched alkyl group having 1 to 10 carbon atoms, an aryl group having 4 to 16 carbon atoms, or a (meth)acryloyloxyalkylene group. The alkyl group preferably has 1 to 6 carbon atoms. The aryl group preferably has 5 to 8 carbon atoms. The aryl group is preferably a phenyl group. The alkylene group contained in the (meth)acryloyloxyalkylene group has, for example, 1 to 10 carbon atoms, preferably 1 to 3 carbon atoms. The (meth)acryloyloxyalkylene group is preferably a (meth)acryloyloxyethylene group.

[0061] a 3 is 0 or 1. 3 When it is 0, P and Q 2 The oxygen atom to which it is bonded is O - .

[0062] Q 3 It is a linear or branched alkylene group having 1 to 10 carbon atoms, or a linear or branched alkyleneoxyalkylene group having 1 to 10 carbon atoms.

[0063] In addition to being bonded to the first phosphate, the first bismuth compound may also be bonded to other compounds. The bonding between bismuth and other compounds may be any of an ionic bond, a coordination bond, and a covalent bond. That is, the first bismuth compound may be bismuth (Bi 3+ Or Bi 5+ ) as a cation and the first phosphate ester and other compounds as anions of the phosphate or complex salt, which can be either a phosphate compound or a complex.

[0064] Specific examples of other compounds include at least one selected from the group consisting of salicylic acid and (meth)acrylic acid.

[0065] Regarding the ratio of the first phosphate ester to other compounds, in order to improve the solubility in the free radical polymerizable compound, the other compounds are preferably 0.1 to 10 moles, more preferably 0.1 to 5 moles, further preferably 0.1 to 1 mole, and particularly preferably 0.1 to 0.5 moles relative to 1 mole of the first phosphate ester. It should be noted that when there are two or more first phosphate esters, the above range is based on the total molar number of the first phosphate esters.

[0066] The bonding between the first phosphate and bismuth can be confirmed by infrared spectroscopy (IR) analysis. That is, in the infrared spectroscopy measurement of the first bismuth compound, for example, at 1670 to 1700 cm -1 When a peak is confirmed at , it can be confirmed that the first phosphate and bismuth have been bound. It can be considered that this peak is a characteristic peak of Bi-OP stretching vibration. This peak is not confirmed for bismuth and the first phosphate before binding.

[0067] The IR spectrum is measured using, for example, Spectrum One manufactured by PerkinElmer, Inc., by a single reflection ATR method and four-time integration.

[0068] In addition, by combining elemental analysis based on NMR (nuclear magnetic resonance spectroscopy), MALDI-TOF-MS (matrix-assisted laser desorption ionization-time of flight mass spectrometry), XPS (X-ray photoelectron spectroscopy) and EDS (energy dispersive X-ray spectroscopy), the bonding number of salicylic acid or (meth) acrylic acid and each phosphate in the first bismuth compound can be confirmed.

[0069] exist 1 H-, 31 In the P-NMR measurement, a nuclear magnetic resonance apparatus (JNM-ECA400II manufactured by JEOL Ltd.) was used, deuterated acetone was used as a solvent, and the measurement was performed at a sample concentration of 1 mass %.

[0070] In the XPS measurement, an X-ray photoelectron spectrometer (ESCA5701ci / MC manufactured by ULVAC-PHI INCORPORATED.) was used, and monochromated Al-Kα (14 kV-330 W) was used as the X-ray source, and the grating diameter was φ800 μm and the photoelectron emission angle was 45 degrees. The sample was pulverized in an agate mortar, and the obtained powder was fixed on a substrate with carbon tape and introduced into the measurement chamber for measurement.

[0071] The first bismuth compound is, for example, a phosphate or a complex salt represented by the following formula (1).

[0072]

[0073] In the above formula (1), Q 1, Q 2 , Q 3 and a 3 The same as the above formula (2).

[0074] In the above formula (1), X is (meth)acrylic acid represented by the following formula (1a) or salicylic acid represented by the following formula (1b). X is preferably salicylic acid represented by the following formula (1b).

[0075]

[0076] a 1 A number greater than 0 and less than 1.

[0077] a 2 A number greater than or equal to 0.1 and less than or equal to 3.

[0078] a 1 +a 2 A number greater than 2 and less than 3.

[0079] For example, the first bismuth compound can be confirmed to have the structure represented by the above formula (1) by detecting the protonated molecular ion or sodium adduct ion of the compound in MALDI-TOF-MS measurement. 1 is a number from 1 to 2, X is salicylic acid, a 2 A number from 1 to 3, Q 1 Methyl, Q 2 is a methacryloyloxyalkyl group, Q 3 When a compound having a straight-chain alkyl group having 2 carbon atoms was measured, a protonated ion of m / z=667 was detected.

[0080] In the MALDI-TOF-MS measurement, a rapiflex TOF / TOF model manufactured by Bruker was used, CHCA (α-cyano-4-hydroxycinnamic acid), DIT (Dithranol), and DHB (2,5-Dihydroxybenzoic acid) were used as matrices, and sodium trifluoroacetate was used as a cationizing agent. The measurement was performed in the reflector / positive mode, and the mass range was set to m / z = 20 to 4000.

[0081] The first bismuth compound may be a mixture of a plurality of first phosphates and a plurality of other compounds bonded to bismuth. The first bismuth compound preferably has a first phosphate having one (meth)acryloyl group and a first phosphate having two (meth)acryloyl groups bonded to bismuth. Such a first bismuth compound tends to have high compatibility with a polymerizable compound.

[0082] In the first bismuth compound, the ratio of the first phosphate having two (meth)acryloyl groups is preferably 0.05 to 3 mol, more preferably 0.10 to 2 mol, and even more preferably 0.15 to 1 mol per 1 mol of the first phosphate having one (meth)acryloyl group.

[0083] Preferred first bismuth compounds include those represented by the following formulae (III) to (V).

[0084]

[0085]

[0086]

[0087] In the formula, R is independently a hydrogen atom or a methyl group.

[0088] In the above formula (III), a+x+y+z=3. x represents the number of moles of 2-((meth)acryloyloxy)ethyl hydrogen phosphate residues. y represents the number of moles of phenyl-2-((meth)acryloyloxy)ethyl phosphate residues. z represents the number of moles of bis[2-((meth)acryloyloxy)ethyl]phosphate residues. a represents the number of moles of (meth)acrylic acid residues.

[0089] In the above formula (IV), 2b+u+v+w=3. u represents the number of moles of 2-((meth)acryloyloxy)ethyl hydrogen phosphate residue. v represents the number of moles of phenyl-2-((meth)acryloyloxy)ethyl phosphate residue. w represents the number of moles of bis[2-((meth)acryloyloxy)ethyl]phosphate residue. b represents the number of moles of salicylic acid residue.

[0090] In the above formula (V), 2c+q+r+2s+t=3. q represents the number of moles of 2-((meth)acryloyloxy)ethyl hydrogen phosphate residue. r represents the number of moles of phenyl-2-((meth)acryloyloxy)ethyl phosphate residue. s represents the number of moles of 2-((meth)acryloyloxy)ethyl phosphate residue. t represents the number of moles of bis[2-((meth)acryloyloxy)ethyl] phosphate residue. c represents the number of moles of salicylic acid residue.

[0091] It should be noted that the first bismuth compounds represented by the above formulae (III) to (V) are not single compounds but may be a mixture of a plurality of compounds. In this case, the molar number of each residue represents the molar number of the entire mixture.

[0092] In the above formula (III), considering that the first bismuth compound can be produced at a low temperature and has less coloring, when a=0, x:y:z=1:0.05-3:0.5-30 is preferred, x:y:z=1:0.1-2:1-20 is more preferred, and x:y:z=1:0.15-1:1.5-10 is further preferred. In addition, from the viewpoint of further reducing coloring, a=0 and y=0 may be used.

[0093] In the above formula (III), except for the case where a=0, preferably a:(x+y+z)=0.1 to 10:1, more preferably a:(x+y+z)=0.1 to 5:1, and further preferably a:(x+y+z)=0.1 to 1:1. In this case, preferably x:y:z=1:0.05 to 3:0.5 to 30, more preferably x:y:z=1:0.1 to 2:1 to 20, and further preferably x:y:z=1:0.15 to 1:1.5 to 10.

[0094] In the above formula (IV), when b=0, the same applies as in the above definition except that x is replaced by u, y is replaced by v, and z is replaced by w.

[0095] In the above formula (IV), except for the case where b=0, preferably b:(u+v+w)=1:0.1 to 30, more preferably b:(u+v+w)=1:0.2 to 20, further preferably b:(u+v+w)=1:0.3 to 10, and particularly preferably b:(u+v+w)=1:0.5 to 5. In this case, preferably u:v:w=1:0.05 to 20:0.1 to 40, more preferably u:v:w=1:0.1 to 10:0.2 to 20, and further preferably u:v:w=1:0.2 to 5:0.4 to 10.

[0096] In the above formula (IV), when c=0, preferably q:r:s:t=1: 0.1-50: 0.05-20: 0.1-40, more preferably q:r:s:t=1: 0.3-30: 0.1-10: 0.2-20, and further preferably q:r:s:t=1: 0.5-20: 0.2-5: 0.4-10.

[0097] In the above formula (V), except for the case where c=0, preferably c:(q+r+s+t)=1:0.1 to 30, more preferably c:(q+r+s+t)=1:0.2 to 20, further preferably c:(q+r+s+t)=1:0.3 to 10, and particularly preferably c:(q+r+s+t)=1:0.5 to 5. In this case, preferably q:r:s:t=1:0.1 to 50:0.05 to 20:0.1 to 40, more preferably q:r:s:t=1:0.3 to 30:0.1 to 10:0.2 to 20, and further preferably q:r:s:t=1:0.5 to 20:0.2 to 5:0.4 to 10.

[0098] The first bismuth compound is, for example, a phosphate or a complex salt represented by the following formula (3).

[0099]

[0100] In the above formula (3), Q 1 , Q 2 , Q 3 and a 3 The same as the above formula (2).

[0101] a 4 A number greater than 0 and less than 3.

[0102] a 5 A number greater than 0 and less than 3.

[0103] a 4 +a 5 is 3.

[0104] In addition, the first bismuth compound may be a composition containing compounds other than the first bismuth compound. Hereinafter, this composition is also referred to as the first bismuth composition. The first bismuth composition may also contain a phosphate compound or unreacted raw materials produced as a by-product during production.

[0105] Industrially, it takes a lot of effort to remove these by-produced phosphate compounds or unreacted raw materials from the first bismuth compound. In addition, these by-produced phosphate compounds or unreacted raw materials may contribute to improving the solubility of the radical polymerizable monomer.

[0106] Examples of the by-produced phosphoric acid compound include a dimer of phosphoric acid ester having one (meth)acryloyl group (monophosphate), a dimer of phosphoric acid ester having two (meth)acryloyl groups (diester), and an ester of bismuth salicylate or bismuth (meth)acrylate and phosphoric acid.

[0107] Examples of the unreacted raw material include phosphoric acid esters having one (meth)acryloyl group (monophosphate), phosphoric acid esters having two (meth)acryloyl groups (diester), bismuth salicylate, and bismuth (meth)acrylate.

[0108] In the first bismuth composition, the proportion of compounds other than the first bismuth compound is, for example, 30% by mass or less. This proportion has no lower limit, and is 0% by mass in one example and 5% by mass in another example. This proportion can be adjusted by using 1 The by-produced phosphoric acid compound and the unreacted raw material in the first bismuth composition were quantitatively confirmed by the internal standard method of H MNR.

[0109] In addition, the first bismuth composition may also contain a compound derived from bismuth oxide. The compound derived from bismuth oxide is, for example, a compound formed by bonding bismuth oxide to a phosphate ester, (meth) acrylic acid and / or salicylic acid having a (meth) acryloyl group. Although the structure of the compound derived from bismuth oxide is unclear, it can be considered that the hydroxyl group formed on the surface of bismuth oxide is combined with the carboxyl group of the phosphate ester, (meth) acrylic acid or salicylic acid. It should be noted that it is very difficult to separate the compound derived from bismuth oxide from the first bismuth compound. Therefore, in the case where a compound derived from bismuth oxide is produced as a byproduct, it is preferably used in a state containing a compound derived from bismuth oxide. In the case where a compound derived from bismuth oxide is produced as a byproduct, it is preferably adjusted to the manufacturing conditions, etc. so that its amount is within a range that does not reduce the solubility of the first bismuth composition. It should be noted that the inclusion of a compound derived from bismuth oxide can be comprehensively judged by its manufacturing conditions or methods such as IR, NMR, and XPS.

[0110] [Method for producing the first bismuth compound]

[0111] The method for producing the first bismuth compound is not particularly limited, but is preferably produced by reacting the second bismuth compound with the first phosphate ester. Specifically, it is preferably produced by reacting the second bismuth compound with the first phosphate ester in an aliphatic hydrocarbon solvent or an aromatic solvent, adding a polymerization inhibitor as needed, and then dehydrating the second bismuth compound.

[0112] The second bismuth compound is an organic compound containing bismuth. The second bismuth compound contains bismuth (meth)acrylate or bismuth subsalicylate. There are no particular limitations on the bismuth (meth)acrylate or bismuth subsalicylate, and commercially available ones can be used.

[0113] It should be noted that bismuth subsalicylate is a compound in which salicylic acid is bonded to bismuth, and is represented by the following formula (VI).

[0114]

[0115] The method for producing bismuth subsalicylate is not particularly limited, and bismuth subsalicylate can be produced by a known method.

[0116] As the first phosphoric acid ester, a commercially available substance can be used. The first phosphoric acid ester may be a phosphoric acid ester having one (meth)acryloyl group, a phosphoric acid ester having two (meth)acryloyl groups, or a mixture thereof.

[0117] As a phosphoric acid ester which has one (meth)acryloyl group, 2-(methacryloyloxy)ethyl dihydrogen phosphate, diphenyl-2-methacryloyloxyethyl phosphate, etc. are mentioned, for example.

[0118] Moreover, as a phosphoric acid ester which has two (meth)acryloyl groups, bis[2-(methacryloyloxy)ethyl] hydrogen phosphate, [2-(methacryloyloxy)ethyl]phenyl hydrogen phosphate, etc. are mentioned, for example.

[0119] In addition, as the first phosphate ester, in order to improve compatibility, it is preferred to add a phosphate triester such as diphenyl-2-methacryloyloxyethyl phosphate, phenyl bis[2-(methacryloyloxyethyl)] phosphate, tris[2-(methacryloyloxyethyl)] phosphate. If a phosphate triester having a phenyl group is used, the monovalent phenyl phosphate diester having one (meth)acryloyl group in the above formulas (III) to (V) can be well introduced.

[0120] The amount of the triester phosphate used is preferably 0.1 to 20 mol, more preferably 0.2 to 5 mol, based on 1 mol of the total of the phosphate ester having one (meth)acryloyl group and the phosphate ester having two (meth)acryloyl groups.

[0121] The amount of the first phosphoric acid ester used may be determined so as to obtain the desired first bismuth compound. Specifically, the amount of the first phosphoric acid ester used is preferably in the range of 0.3 to 10 mol per 1 mol of the second bismuth compound.

[0122] (Aliphatic hydrocarbon solvent or aromatic solvent)

[0123] In this embodiment, the second bismuth compound and the first phosphate are preferably stirred and mixed in an aliphatic hydrocarbon solvent or an aromatic solvent and reacted. At this time, water is generated in the reaction system, so it is preferred to dehydrate the generated water. In order to make the generated water easy to dehydrate, it is preferred to use an aliphatic hydrocarbon solvent or an aromatic solvent with a high boiling point, specifically a boiling point of 100° C. or more. It is also possible to mix an aliphatic hydrocarbon solvent with an aromatic solvent and use it as a mixed solvent.

[0124] Examples of the aliphatic hydrocarbon solvent or aromatic solvent include hexane, heptane, nonane, decane, undecane, dodecane, xylene, dimethoxybenzene and isomers thereof; benzene, toluene, chlorobenzene, bromobenzene, anisole; petroleum ether, petroleum benzene, benzoin, and the like.

[0125] The amount of the aliphatic hydrocarbon solvent or aromatic solvent used is not particularly limited as long as it is an amount that can fully mix the second bismuth compound and the first phosphate ester. Considering the productivity of the first bismuth compound, the aliphatic hydrocarbon solvent or aromatic solvent is preferably used in a ratio of 5 to 100 mL per 1 g of the second bismuth compound.

[0126] (Reaction Conditions)

[0127] The method of introducing the second bismuth compound and the first phosphate into the reaction system is not particularly limited. For example, a method of adding the second bismuth compound optionally diluted with an aliphatic hydrocarbon solvent or an aromatic solvent together with the first phosphate optionally diluted with an aliphatic hydrocarbon solvent or an aromatic solvent to the reaction system and stirring and mixing can be adopted. In addition, a method of pre-introducing an aliphatic hydrocarbon solvent or an aromatic solvent into the reaction system, adding the second bismuth compound optionally diluted with an aliphatic hydrocarbon solvent or an aromatic solvent together with the first phosphate optionally diluted with an aliphatic hydrocarbon solvent or an aromatic solvent and stirring and mixing can also be adopted. In addition, a method of pre-introducing one component into the reaction system, and then introducing another component into the reaction system and stirring and mixing can also be adopted. Among them, in order to reduce the coloring of the obtained first bismuth compound and improve productivity, the following method is preferably adopted. First, the second bismuth compound is dispersed in an aliphatic hydrocarbon solvent or an aromatic solvent. At this time, the second bismuth compound may not be dissolved. In this case, it is preferred to crush the block of the second bismuth compound using an ultrasonic device, so that the block no longer exists. Thereafter, the first phosphoric acid ester is added to the turbid solution in which the second bismuth compound is dispersed, and stirring and heating are started.

[0128] The temperature (reaction temperature) when stirring the components may be the reflux temperature of the aliphatic hydrocarbon solvent or the aromatic solvent. In order to further reduce the coloration of the obtained first bismuth compound, it is ideally carried out at an oil bath temperature of 30 to 150° C., more preferably at a temperature of 40 to 140° C., and even more preferably at a temperature of 45 to 120° C.

[0129] In addition, when the reaction temperature is 30 to 110° C., in order to remove (dehydrate) the water generated in the reaction system, it is preferred to set the reaction system under reduced pressure. At this time, the second bismuth compound and the first phosphate can be mixed while dehydrating, or the two can be mixed before dehydrating. However, considering the efficiency of the reaction, it is preferred to dehydrate the two after mixing them while reacting them.

[0130] The reaction time is not particularly limited, but is usually 1 hour to 6 hours.

[0131] In consideration of operability, the reaction may be carried out in any of an air atmosphere, an inert gas atmosphere, and a dry air atmosphere. In consideration of operability, the reaction is preferably carried out in an air atmosphere.

[0132] After the reaction is carried out under the above conditions, the solvent is distilled off the obtained first bismuth compound and concentrated. Subsequently, when there is an insoluble turbid component, it is preferably separated by filtration or centrifugation. Furthermore, a solvent that is soluble in the reaction solvent used but does not dissolve the first bismuth compound is added to the concentrated reaction solution obtained by this treatment, and reprecipitation and purification are performed. In the case where a high boiling point solvent remains, the above decantation operation is repeated to replace the solvent. Thereafter, the residual solvent is distilled off and vacuum drying is performed to obtain the first bismuth compound.

[0133] In the curable composition of the present embodiment, the content of the first bismuth compound is, for example, 20% by mass or more and 90% by mass or less. When the content of the first bismuth compound is high, there is a tendency for the X-ray shielding effect of the cured product to be improved. The content of the first bismuth compound is preferably 50% by mass or more, more preferably 60% by mass or more, and further preferably 65% ​​by mass or more. On the other hand, if the content of the first bismuth compound is too much, there is a concern that the odor of the cured product will be enhanced. The content of the first bismuth compound is preferably 80% by mass or less.

[0134] <First polymerizable compound>

[0135] The first polymerizable compound contains at least one polymerizable group selected from the group consisting of an acryloyl group, a methacryloyl group, a vinyl group, and an allyl group, and has a boiling point of 90° C. or higher at 1 atmosphere.

[0136] The boiling point of the first polymerizable compound is preferably 100° C. or higher, more preferably 140° C. or higher. When the boiling point of the first polymerizable compound is high, the odor of the cured product tends to decrease. The boiling point of the first polymerizable compound is not particularly limited, but is 200° C. or lower according to one example, and 300° C. or lower according to another example. The boiling point of the first polymerizable compound can be measured, for example, by thermogravimetric (TG) analysis.

[0137] In the TG measurement, a differential thermal / thermogravimetric simultaneous measurement apparatus (TG8120 manufactured by Rigaku Corporation) was used, and the temperature was scanned from room temperature to 500° C. at a heating rate of 10° C. / min under air flow.

[0138] The content of the first polymerizable compound in the curable composition is, for example, 10% by mass or more and 80% by mass or less. 1The content is measured by H NMR. The measurement conditions of H NMR are the same as above.

[0139] The first polymerizable compound preferably includes a monofunctional free radical polymerizable compound having one free radical polymerizable site in one molecule. When the curable composition includes a monofunctional free radical polymerizable compound, there is a tendency for the compatibility of the first bismuth compound to be improved. The boiling point of the monofunctional free radical polymerizable compound is preferably 150° C. or higher, more preferably 180° C. or higher.

[0140] Examples of the monofunctional radical polymerizable compound having an acryloyl group include various commercially available polymerizable compounds such as acrylic acid, acrylamide, phenyl acrylate, benzyl acrylate, isobutyl acrylate, methoxyethyl acrylate, ethoxyethyl acrylate, tetrahydrofurfuryl acrylate, isocyanate ethyl acrylate, and acryloyloxymethyltrimethoxysilane.

[0141] Examples of the monofunctional radical polymerizable compound having a methacryloyl group include various commercially available polymerizable compounds such as methacrylic acid, methacrylamide, phenyl methacrylate, benzyl methacrylate, isobutyl methacrylate, methoxyethyl methacrylate, ethoxyethyl methacrylate, and methacryloxymethyltrimethoxysilane.

[0142] Examples of monofunctional free radical polymerizable compounds having a vinyl group include various commercially available polymerizable compounds such as vinylpyridine, vinylpyrrolidone, styrene, and styrene derivatives. Examples of styrene derivatives include methylstyrene and its structural isomers, methoxystyrene and its structural isomers, methylstyrene dimer, chlorostyrene, bromostyrene, and divinylbenzene.

[0143] Examples of the monofunctional radical polymerizable compound having an allyl group include various commercially available polymerizable compounds such as allyl methyl carbonate, allyl phenyl ether, 4-allyloxytoluene, allyloxytrimethylsilane, allyl benzoate, allyl methacrylate, and allyl glycidyl ether.

[0144] As a suitable monofunctional radical polymerizable compound, from the viewpoint of optical properties and impact resistance after curing, there can be mentioned (meth)acrylate represented by the following formula (I).

[0145]

[0146] In the above formula (I), R 1It is a hydroxyl group, a straight-chain or branched alkyl group having 1 to 10 carbon atoms, a straight-chain or branched alkoxy group having 1 to 10 carbon atoms, a cycloalkyl group having 4 to 10 carbon atoms, a heterocycloalkyl group having 3 to 10 carbon atoms and 1 to 3 heteroatoms, an aryl group having 4 to 10 carbon atoms, or a heteroaryl group having 3 to 10 carbon atoms and 1 to 3 heteroatoms.

[0147] R 1 Preferably, it is a straight-chain or branched alkyl group having 1 to 10 carbon atoms, a straight-chain or branched alkoxy group having 1 to 10 carbon atoms, or a heterocycloalkyl group having 3 to 10 carbon atoms and 1 to 3 heteroatoms; more preferably, it is a straight-chain or branched alkoxy group having 1 to 10 carbon atoms, or a heterocycloalkyl group having 3 to 10 carbon atoms and 1 to 3 heteroatoms; further preferably, it is a methoxy group or a tetrahydrofuranyl group.

[0148] R 2 It is a linear or branched alkylene group having 1 to 10 carbon atoms, or an alkyleneoxy group having 1 to 10 carbon atoms.

[0149] R 2 It is preferably a linear or branched alkylene group having 1 to 10 carbon atoms, and more preferably a methylene group or an ethylene group.

[0150] R 3 A hydrogen atom or a methyl group.

[0151] a is 0 or 1. a is preferably 1.

[0152] Specific examples of the (meth)acrylate represented by the above formula (I) include at least one selected from the group consisting of methoxyethyl acrylate (MEMA), ethoxyethyl acrylate, methoxyethyl methacrylate, ethoxyethyl methacrylate, tetrahydrofurfuryl acrylate (THFAA) and tetrahydrofurfuryl methacrylate (THFMA).

[0153] In the curable composition of the present embodiment, the ratio of the monofunctional free radical polymerizable compound is preferably 10% by mass or more and 80% by mass or less. When the ratio is high, there is a tendency that the compatibility of the first bismuth compound is improved. When the ratio is low, the odor of the cured product is reduced, and there is also a tendency that the impact resistance is improved. The ratio is more preferably 10% by mass or more and 30% by mass or less. For example, the ratio can be measured by NMR.

[0154] The curable composition of the present embodiment preferably includes a plurality of monofunctional free radical polymers. When a plurality of monofunctional free radical polymers are included, there is a tendency for the compatibility of the first bismuth compound to be improved. The curable composition of the present embodiment may also include a monofunctional free radical polymerizable compound having a (meth) acryloyl group and a monofunctional free radical polymerizable compound having a vinyl group. The ratio M4 / M5 of the mass M4 of the monofunctional free radical polymerizable compound having a (meth) acryloyl group to the mass M5 of the monofunctional free radical polymerizable compound having a vinyl group is, for example, 0.1 or more and 10 or less, preferably 1 or more and 5 or less.

[0155] The curable composition of this embodiment preferably contains two or more (meth)acrylates represented by the above formula (I), and more preferably contains R 1 is a furanyl (meth)acrylate and R in the above formula (I) 1 At least one of the (meth)acrylates containing methoxy groups. 1 When the (meth)acrylate is a furanyl group, the compatibility of the first bismuth compound tends to be improved. 1 When it is a (meth)acrylate with a methoxy group, the hardness of the cured product tends to be improved. 1 It is a methoxy (meth)acrylate. 1 The mass of methoxy (meth)acrylate M6 and R 1 The ratio M6 / M7 of the mass M7 of the (meth)acrylate being a furanyl group is preferably 0.1 or more and 10 or less. When the ratio M6 / M7 is within this range, the compatibility of the first bismuth compound in the curable composition is improved, and the hardness of the cured product can be improved. The ratio M6 / M7 is more preferably 0.3 or more and 5 or less, and further preferably 0.5 or more and 3 or less.

[0156] The ratio M1 / M2 of the mass M1 of the first bismuth compound to the mass M2 of the monofunctional free radical polymerizable compound is preferably 0.25 or more and 100 or less. When the ratio is high, there is a tendency for the X-ray shielding performance of the cured product to be improved. When the ratio is low, there is a tendency for the compatibility of the first bismuth compound to be improved. The ratio is more preferably 1 or more and 6 or less.

[0157] In addition, the first polymerizable compound also preferably includes a polyfunctional free radical polymerizable compound having multiple free radical polymerizable sites in one molecule. When a polyfunctional free radical polymerizable compound is included, the mechanical properties of the cured product of the curable composition, such as impact resistance, can be further improved. As the polyfunctional free radical polymerizable compound, commercially available substances can be used without limitation. The boiling point of the polyfunctional free radical polymerizable compound is preferably above 100°C, more preferably above 140°C. In addition, the number average molecular weight of the polyfunctional free radical polymerizable compound obtained by gel permeation chromatography analysis is preferably above 90 and below 2000, more preferably above 250 and below 1800.

[0158] As the polyfunctional radical polymerizable compound, a di(meth)acrylate represented by the following formula (II) is preferably used in consideration of solubility, viscosity as a composition, and impact resistance of a cured product.

[0159]

[0160] In the above formula (II), R 4 It is a linear or branched alkylene group having 1 to 10 carbon atoms, or a linear or branched alkyleneoxy group having 1 to 10 carbon atoms.

[0161] R 4 It is preferably a linear or branched alkyleneoxy group having 1 to 10 carbon atoms, and more preferably an ethyleneoxy group.

[0162] R 5 and R 6 are each independently a hydrogen atom or a methyl group.

[0163] n is a number of 1 to 50. n is preferably a number of 3 to 30.

[0164] Specific examples of the di(meth)acrylate represented by the above formula (II) include bifunctional (meth)acrylates selected from the group consisting of polyethylene glycol dimethacrylate, polyethylene glycol diacrylate, polypropylene glycol dimethacrylate, polypropylene glycol diacrylate, polytetramethylene glycol dimethacrylate, and polytetramethylene glycol diacrylate.

[0165] In the curable composition of the present embodiment, the proportion of the multifunctional free radical polymerizable compound is preferably 1% by mass or more and 50% by mass or less. When the proportion is high, there is a tendency for the impact resistance of the cured product to be improved. When the proportion is low, there is a tendency for the compatibility of the first bismuth compound to be improved. The proportion is more preferably 5% by mass or more and 20% by mass or less. For example, the proportion can be measured by NMR. The measurement conditions of NMR are the same as above.

[0166] The ratio M1 / M3 of the mass M1 of the first bismuth compound to the mass M3 of the multifunctional free radical polymerizable compound is preferably 0.1 or more and 100 or less. When the ratio is high, there is a tendency for the X-ray shielding performance of the cured product to be improved. When the ratio is low, there is a tendency for the impact resistance of the cured product to be improved. The ratio is more preferably 1 or more and 10 or less.

[0167] The curable composition of the present embodiment preferably includes both a monofunctional free radical polymerizable compound and a polyfunctional free radical polymerizable compound. The ratio M2 / M3 of the mass M2 of the monofunctional free radical polymerizable compound to the mass M3 of the polyfunctional free radical polymerizable compound is preferably 0.1 or more and 300 or less. When the ratio is high, there is a tendency for the compatibility of the first bismuth compound to be improved. When the ratio is low, there is a tendency for the impact resistance of the cured product to be improved. The ratio is more preferably 0.1 or more and 10 or less.

[0168] The curable composition of this embodiment preferably contains R 1 is a furanyl (meth)acrylate, R in the above formula (I) 1 The (meth)acrylate is a methoxy group, and the di(meth)acrylate represented by the above formula (II). By including these three polymerizable compounds, a cured product with reduced odor and better impact resistance can be obtained. 1 The mass M6 and R of methoxy (meth)acrylate 1 The ratio M8 / M9 of the total mass M8 of the mass M7 of the (meth)acrylate being a furyl group to the mass M9 of the di(meth)acrylate represented by the above formula (II) is preferably 0.1 to 10, more preferably 0.3 to 5, and even more preferably 0.5 to 3.

[0169] The curable composition of the present embodiment may also include 10% by mass or less of a nitrile compound. The content of the nitrile compound in the curable composition is preferably 5% by mass or less, more preferably 3% by mass or less, and further preferably 1% by mass or less. When the content of the nitrile compound is small, there is a tendency for the odor of the cured product to decrease. For the lower limit of the content of the nitrile compound, according to one example, it is 100% by mass or more, and according to another example, it is 0% by mass. For example, it can be obtained by 1 The ratio is measured by H NMR. The measurement conditions of H NMR are the same as above.

[0170] Examples of the nitrile compound include acrylonitrile, methacrylonitrile, crotononitrile, 2-chloroacrylonitrile, 2-cyanoethyl acrylate, allyl nitrile, allyl cyanoacetate, fumaronitrile, and 5-norbornene-2-carbonitrile.

[0171] The curable composition of this embodiment may also contain a second polymerizable compound having a boiling point of less than 90°C at 1 atmosphere. The content of the second polymerizable compound in the curable composition is preferably 20% by mass or less, more preferably 10% by mass or less, and further preferably 5% by mass or less. When the content of the second polymerizable compound is small, there is a tendency for the odor of the cured product to decrease. The lower limit of the content of the second polymerizable compound is 1% by mass or more according to one example and 0% by mass according to another example. For example, 1 This ratio is determined by H MNR.

[0172] Examples of the second polymerizable compound include methyl acrylate, allyl methyl ether, and allyl ethyl ether.

[0173] Regarding the blending ratio of the total amount of polymerizable compounds other than the first bismuth compound in the curable composition of the present embodiment (hereinafter also referred to as the total amount of polymerizable compounds) and the first bismuth compound, in consideration of X-ray blocking effect, dispersibility, coloring reduction effect, etc., the total amount of polymerizable compounds is preferably 1 to 500 parts by mass, preferably 5 to 300 parts by mass, and more preferably 10 to 200 parts by mass per 100 parts by mass of the first bismuth compound.

[0174] <Other compounding agents>

[0175] The curable composition of the present embodiment may contain, in addition to the first bismuth compound and the first polymerizable compound, a known compounding agent that can be generally mixed into a free radical polymerizable curable composition. Examples of such compounding agents include free radical polymerization initiators, antioxidants, mold release agents for improving mold release properties, pigments for adjusting the color tone of the cured product, and chain transfer agents for controlling polymerizability.

[0176] The content of each compounding agent may be within a range that does not inhibit the effects of the present invention. Specifically, each compounding agent is preferably added in an amount of 0 to 30 parts by mass, more preferably 0.01 to 20 parts by mass, and even more preferably 0.02 to 15 parts by mass per 100 parts by mass of the first bismuth compound and the first polymerizable compound.

[0177] The curable composition of the present embodiment can be produced by mixing the first bismuth compound, the first polymerizable compound, and various compounding agents that are optionally compounded.

[0178] "Solidified Object"

[0179] The cured product of the present embodiment is formed by curing the curable composition of the present embodiment. As a method for manufacturing the cured product, a known method can be used. Specifically, photopolymerization, thermal polymerization, or both polymerization methods can be used. The appropriate polymerization method is determined based on the free radical polymerization initiator that is optionally mixed.

[0180] <Physical properties of cured product>

[0181] The solidified material of this embodiment contains bismuth with high X-ray blocking ability at a high concentration, has high transmittance, and has little coloration. For example, in the case of a thickness of 2 mm, the transmittance of the solidified material at a wavelength of 560 nm is 80% or more, the X-ray blocking ability is equivalent to or exceeds 0.02 mm lead foil, and the yellow index is 40 or less.

[0182] Furthermore, when the total mass of the cured product is 100 mass %, the ratio of bismuth contained in the cured product can be set to 5 to 40 mass %.

[0183] The IR spectrum of the cured product can be found at 1670-1700 cm -1 The peak may be derived from Bi-OP bonding.

[0184] <Application of Cured Material>

[0185] The cured product of this embodiment is transparent and lightly colored, and thus can be used as an optical article. Furthermore, although it is visible light transmissive, it has radiation blocking properties, and thus can be used as a transparent radiation shielding material.

[0186] The optical article obtained using the cured product of this embodiment can be used as a radiation shielding window material or a radiation shielding lens.

[0187] Furthermore, the lens obtained using the cured product of this embodiment can be used as radiation shielding glasses or radiation shielding goggles.

[0188] Example

[0189] Hereinafter, the present invention will be described in detail using Examples and Comparative Examples, but the present invention is not limited to the following Examples.

[0190] <Production Example 1: Production of First Bismuth Compound>

[0191] In a 1000 mL eggplant-shaped flask were placed 94.27 g of bismuth (III) subsalicylate (manufactured by Sigma-Aldrich, 260.35 mmol in terms of bismuth), 33.06 g of a mixture of bis[(2-methacryloyloxyethyl)]phosphate as a phosphoric diester and (2-methacryloyloxyethyl)phosphate as a phosphoric monoester (manufactured by Daihachi Chemical Industry Co., Ltd., MR-200, phosphoric acid value 162.04 mmol), 33.09 g of diphenyl-2-methacryloyloxyethyl phosphate as a phosphoric triester (manufactured by Daihachi Chemical Industry Co., Ltd., MR-260, 91.33 mmol), and 6.17 g of butylated hydroxytoluene (BHT, manufactured by Fujifilm Wako Pure Chemical Corporation, special grade reagent) as a polymerization inhibitor, and 750 mL of toluene was added. The product was ultrasonically dispersed using a bath-type ultrasonic cleaning machine to produce a turbid solution.

[0192] The obtained turbid solution was transferred to a 1000 mL four-necked flask equipped with a Dean-Stark trap, and the reaction was carried out while heating and stirring at 130°C in an oil bath, and the generated water was discharged out of the system. The time when no more water was generated was regarded as the end point of the reaction. A light yellow scattering solution with a small amount of light yellow precipitate was obtained.

[0193] The solution was concentrated to 250 mL using a vacuum evaporator. 8 g of alumina powder was added and allowed to stand overnight, then suction filtered with 5B filter paper. 3 g of activated carbon (Darco G60 manufactured by Norit) was added to the obtained light yellow scattered filtrate, and placed in a centrifuge at 23830 × g for 8 hours. The centrifugal supernatant was pressure filtered using a membrane filter with a pore size of 0.2 μm to obtain a light yellow transparent filtrate. The solvent was distilled off from the solution using a vacuum evaporator, and then dissolved in 250 mL of acetone. 3 g of activated carbon (Norit SX-Plus manufactured by Norit) was added to the obtained light yellow solution, and placed in a centrifuge at 23830 × g for 12 hours. The centrifugal supernatant was pressure filtered using a membrane filter with a pore size of 0.2 μm to obtain a light yellow transparent filtrate. The obtained filtrate was concentrated to 100 mL using a vacuum evaporator. The acetone solution was added to 800 mL of hexane in a 1000 mL conical flask under stirring. The generated white precipitate was filtered out by suction using 5B filter paper, and the obtained solid was vacuum dried. 64.40 g of the first bismuth compound was obtained in the form of a white powder. The synthesis was confirmed by the above-mentioned determination method.

[0194] <Example 1>

[0195] To 70 parts by mass of the first bismuth compound obtained in Preparation Example 1, 10 parts by mass of methoxyethyl methacrylate (hereinafter referred to as "MEMA"), 10.7 parts by mass of tetrahydrofurfuryl acrylate (hereinafter referred to as "THFAA"), and 8 parts by mass of styrene (hereinafter referred to as "ST") as polymerizable compounds were added, and 1 part by mass of α-methylstyrene and 0.3 parts by mass of methylstyrene dimer were added as other compounding agents, and uniformly dissolved to obtain a curable composition. 0.45 parts by mass of 2,2'-azobis(isobutyric acid)dimethyl ester (V-601) and 0.15 parts by mass of 1,1'-azobis(cyclohexane-1-carbonitrile) (V-40) were further added to the curable composition and completely dissolved. The curable composition was placed under reduced pressure using a vacuum pump to remove dissolved oxygen. Thereafter, the curable composition was injected into a 2 mm thick glass mold, and polymerized at a maximum temperature of 100°C for 5 hours to obtain a light yellow transparent cured product. The thickness of the obtained cured product was 2.32 mm.

[0196] <Example 2>

[0197] A pale yellow transparent cured product was obtained by the same operation as in Example 1 except that the amount of MEMA was changed to 18 parts by mass and the addition of ST was omitted. The thickness of the obtained cured product was 2.35 mm.

[0198] <Example 3>

[0199] Tetraethylene glycol dimethacrylate (hereinafter referred to as "4G") 8 parts by mass was added, and ST was omitted. A mixture was obtained by the same method as the preparation method of the curable composition of Example 1. Acetone was added to the mixture and uniformly dissolved, and then the acetone was distilled off under reduced pressure using an evaporator to obtain a curable composition. Except for using the curable composition, the same operation as in Example 1 was performed to obtain a light yellow transparent cured product. The thickness of the cured product was 2.42 mm.

[0200] <Example 4>

[0201] The same operation as in Example 3 was carried out except that nonaethylene glycol dimethacrylate (hereinafter referred to as "9G") was used instead of 4G to obtain a light yellow transparent cured product. The thickness of the obtained cured product was 2.40 mm.

[0202] <Example 5>

[0203] The same operation as in Example 4 was carried out except that tetrahydrofurfuryl methacrylate (hereinafter referred to as "THFMA") was used instead of THFAA. A light yellow cured product having a thickness of 2.46 mm was obtained, but it was not completely transparent.

[0204] <Example 6>

[0205] The same operation as in Example 4 was carried out except that the amount of THFAA was changed to 8.7 parts by mass and the amount of 9G was changed to 10 parts by mass to obtain a light yellow transparent cured product. The thickness of the obtained cured product was 2.20 mm.

[0206] <Example 7>

[0207] A pale yellow transparent cured product was obtained by the same operation as in Example 4 except that the amount of MEMA was changed to 8 parts by mass and the amount of 9G was changed to 10 parts by mass. The thickness of the obtained cured product was 2.23 mm.

[0208] <Example 8>

[0209] A pale yellow transparent cured product was obtained by the same operation as in Example 4 except that the amount of MEMA was changed to 7 parts by mass, the amount of THFAA was changed to 6.7 parts by mass, and the amount of 9G was changed to 15 parts by mass. The thickness of the obtained cured product was 2.48 mm.

[0210] <Example 9>

[0211] A pale yellow transparent cured product was obtained by the same operation as in Example 4 except that the amount of the first bismuth compound was changed to 65 parts by mass, the amount of MEMA was changed to 13 parts by mass, the amount of THFAA was changed to 6.7 parts by mass, and the amount of 9G was changed to 14 parts by mass. The thickness of the cured product was 2.30 mm.

[0212] <Example 10>

[0213] A pale yellow transparent cured product was obtained by the same operation as in Example 4 except that THFMA was used instead of THFAA, the amount of 9G was changed to 5 parts by mass, and 3 parts by mass of methacrylonitrile (hereinafter referred to as "MN") was added. The thickness of the obtained cured product was 2.44 mm.

[0214] <Comparative Example 1>

[0215] The same operation as in Example 4 was carried out except that MN was used instead of MEMA and methyl acrylate (hereinafter referred to as "MA") was used instead of THFAA to obtain a light yellow transparent cured product. The thickness of the obtained cured product was 2.33 mm.

[0216] <Comparative Example 2>

[0217] The same operation as in Comparative Example 1 was carried out except that ST was used instead of MA to obtain a light yellow transparent cured product. The thickness of the obtained cured product was 2.32 mm.

[0218] <Comparative Example 3>

[0219] A pale yellow transparent cured product was obtained by the same operation as in Comparative Example 2 except that the amount of MN was changed to 15.7 parts by mass, the amount of ST was changed to 13 parts by mass, and the addition of 9G was omitted. The thickness of the obtained cured product was 2.18 mm.

[0220] <Comparative Example 4>

[0221] The same operation as in Comparative Example 3 was carried out except that 9G was used instead of ST to obtain a light yellow transparent cured product. The thickness of the obtained cured product was 2.38 mm.

[0222] <Evaluation experiment>

[0223] [Measurement of Viscosity of Curable Composition]

[0224] In the examples and comparative examples, the viscosity of the uniform curable composition obtained by mixing the first bismuth compound and the polymerizable compound was measured by measuring the kinematic viscosity at 25° C. using a Canon-Fenske viscometer and multiplying the viscosity by the density. Alternatively, the viscosity was measured at 25° C. using an E-type viscometer (Rheometer RST manufactured by Brookfield). As a result, the viscosity was in the range of 50 to 100,000 mPa·s.

[0225] [Lead equivalent determination]

[0226] The X-ray blocking ability of the obtained cured product was evaluated by measuring the amount of transmitted X-rays and obtaining the lead equivalent in accordance with Japanese Industrial Standard JIS T61331-1 "Protective equipment against diagnostic X-rays - Part 1: Method for determining material attenuation characteristics". As an X-ray device, MG-45 manufactured by YXLON International was used, the X-ray tube voltage was set to 120 kV, the tube current was set to 12.5 mA, and 2.5 mm Al was used as an additional filter plate. The distance from the focus of the X-ray tube to the sample was set to 600 mm, and the distance from the sample to the measuring machine was set to 900 mm. As a measuring device, an ionization chamber exposure dose rate meter (TOYO MEDIC CO., LTD, RAMTEC-Solo type A4 probe) was used. The X-ray blocking ability was evaluated in the form of lead equivalent (mmPb), which is the thickness (mm) equivalent to the lead plate. As a result, the lead equivalent was 0.10±0.04 mmPb.

[0227] [Determination of odor]

[0228] In order to evaluate the odor of the obtained solidified product, the odor intensity was measured using a portable odor sensor XP-329m manufactured by New Cosmos Electric Co., Ltd. First, a desiccator with an upper horizontal stopcock (manufactured by SIBATA SCIENTIFIC TECHNOLOGY LTD., 017440-150) was connected to the odor sensor with a nylon tube, and the background of the odor sensor was set to zero. The solidified product was left to stand in the desiccator, and the value of the odor sensor after 5 minutes of suction was taken as the odor intensity of the solidified product. The results are shown in Table 1.

[0229] [Impact resistance measurement]

[0230] In order to evaluate the impact resistance of the obtained cured product, a drop ball test was performed. First, a support ring made of NBR was joined to a tube with an inner diameter of 25 mm, an outer diameter of 32 mm, and a height of 25 mm. The thickness of the support ring is 3 mm and the inner diameter is 25 mm. The cured product was allowed to stand on the support ring. A drop device using an electromagnet was used to drop a steel ball from a height of 1.27 m onto the cured product. The weights of the steel balls were 4.5 g, 6.9 g, 14 g, 16 g, 32 g, 50 g, 67 g, 80 g, 95 g, 112 g, 130 g, 151 g, 174 g, 198 g, 225 g, and 261 g. The steel balls were dropped in order from the lightest ones, and the weight of the previous steel ball at which the cured product cracked or broke was taken as the maximum impact resistance. The results are shown in Table 1.

[0231] [Table 1]

[0232]

[0233] The above results show that the odor of the cured product can be reduced by using a polymerizable compound having a boiling point of 90° C. or higher at 1 atmosphere and by using almost no nitrile compound having a nitrile group.

[0234] It is also known that the use of three polymerizable compounds provides higher impact resistance than the use of two high-boiling-point polymerizable compounds. The combination of MEMA, THFAA, and 9G provides the highest impact resistance.

[0235] By adjusting the composition ratio of these three polymerizable compounds, a cured product with high impact resistance and low odor can be obtained, with an odor index of about 100 and a maximum impact resistance of 30 g or more. The cured product can be suitably used as protective glasses.

Claims

1. A curable composition comprising: a first bismuth compound containing bismuth and at least one of an acryloyl group and a methacryloyl group; a first polymerizable compound containing at least one polymerizable group selected from the group consisting of an acryloyl group, a methacryloyl group, a vinyl group, and an allyl group, wherein the first polymerizable compound has a boiling point of 90° C. or higher at 1 atmosphere, The content of the nitrile compound having a nitrile group is less than 10% by mass.

2. The curable composition according to claim 1, wherein The content of the first bismuth compound is 20 mass % or more and 90 mass % or less.

3. The curable composition according to claim 1 or 2, wherein The content of the first polymerizable compound is 10% by mass or more and 80% by mass or less.

4. The curable composition according to claim 1 or 2, wherein The first polymerizable compound includes a monofunctional polymerizable compound having one polymerizable group.

5. The curable composition according to claim 4, wherein The monofunctional polymerizable compound has a boiling point of 100° C. or higher and 300° C. or lower.

6. The curable composition according to claim 4, wherein The monofunctional polymerizable compound includes a monofunctional (meth)acrylate represented by the following formula (I): In the formula (I), R 1 is a hydroxyl group, a linear or branched alkyl group having 1 to 10 carbon atoms, a linear or branched alkoxy group having 1 to 10 carbon atoms, a cycloalkyl group having 4 to 10 carbon atoms, a heterocycloalkyl group having 3 to 10 carbon atoms and 1 to 3 heteroatoms, an aryl group having 4 to 10 carbon atoms, or a heteroaryl group having 3 to 10 carbon atoms and 1 to 3 heteroatoms, R 2 is a linear or branched alkylene group having 1 to 10 carbon atoms, or an alkyleneoxy group having 1 to 10 carbon atoms, R 3 is a hydrogen atom or a methyl group, a is 0 or 1.

7. The curable composition according to claim 4, wherein The monofunctional polymerizable compound includes at least one (meth)acrylate selected from the group consisting of methoxyethyl acrylate, ethoxyethyl acrylate, methoxyethyl methacrylate, ethoxyethyl methacrylate, tetrahydrofurfuryl acrylate, and tetrahydrofurfuryl methacrylate.

8. The curable composition according to claim 1 or 2, wherein The first polymerizable compound includes a multifunctional polymerizable compound having two or more polymerizable groups.

9. The curable composition according to claim 8, wherein The multifunctional polymerizable compound has a number average molecular weight of 90 or more and 2000 or less as analyzed by gel permeation chromatography.

10. The curable composition according to claim 8, wherein The multifunctional polymerizable compound includes a bifunctional (meth)acrylate represented by the following formula (II): In the formula (II), R 4 is a linear or branched alkylene group having 1 to 10 carbon atoms, or a linear or branched alkyleneoxy group having 1 to 10 carbon atoms, R 5 and R 6 are each independently a hydrogen atom or a methyl group, n is a number of 1 or more and 50 or less.

11. The curable composition according to claim 8, wherein The multifunctional polymerizable compound includes a bifunctional (meth)acrylate selected from the group consisting of polyethylene glycol dimethacrylate, polyethylene glycol diacrylate, polypropylene glycol dimethacrylate, polypropylene glycol diacrylate, polytetramethylene glycol dimethacrylate, and polytetramethylene glycol diacrylate. 12 . A cured product, which is a cured product of the curable composition according to claim 1 or 2.

13. An optical article comprising the cured product according to claim 12.

14. A lens comprising the cured product according to claim 12.

15. Spectacles comprising the lens according to claim 14.

Images