Resin composition for lenses, cured material for lenses, and lenses

Abstract

A resin composition for lenses comprising a photocationic polymerization initiator (X) comprising a salt formed from an anion represented by general formula (1) and a cation, and an epoxy compound (Y) comprising two or more epoxy groups in the molecule. (In general formula (1), R1 to R4 each independently represent an alkyl group having 1 to 18 carbon atoms or an aryl group having 6 to 14 carbon atoms.)

Description

Technology Field

[0001] The present invention relates to a resin composition for lenses, a cured material for lenses, and lenses. Background Technology

[0002] Currently, most electronic devices, such as smartphones, tablet terminals, and notebook personal computers, are equipped with cameras. And, along with the miniaturization and high performance of these devices, there is a strong demand for miniaturization and high performance of the lenses of the cameras installed.

[0003] It is known that silicone resin or acrylic resin is used as a material for the lenses of cameras mounted on these electronic devices (Patent Documents 1 and 2). It is also known that epoxy resin is used as a material (Patent Document 3). Prior art literature

[0004] Japanese Patent Publication No. 2008-545553, Japanese Patent Publication No. 2003-131004, Japanese Patent Publication No. 2019-189874 The problem to be solved

[0005] Conventional lens materials had room for improvement in terms of achieving compatibility with the various characteristics required for lenses, such as optical properties and heat resistance.

[0006] The objective of the present invention is to provide a lens resin composition capable of forming a lens cured product having low curing shrinkage, high refractive index, high light transmittance, and high heat resistance.

[0007] In addition, the objective of the present invention is to provide a lens cured material and a lens having low curing shrinkage, high refractive index, high light transmittance, and high heat resistance. means of solving the problem

[0008] The inventors carefully examined the above problem to solve it. As a result, they discovered that the problem could be solved by using a specific photocationic polymerization initiator in combination with an epoxy compound, and thus completed the present invention.

[0009] That is, according to the present invention, a lens resin composition, a lens cured product, and a lens are provided as described below.

[0010] [1]

[0011] A photocationic polymerization initiator (X) comprising an anion represented by general formula (1) and a salt formed from a cation, and

[0012] Epoxy compound (Y) containing two or more epoxy groups within the molecule

[0013] A resin composition for lenses comprising

[0014] [Chemical Formula 1]

[0015]

[0016] (In general formula (1), R 1 ~R 4 Each independently represents an alkyl group having 1 to 18 carbon atoms or an aryl group having 6 to 14 carbon atoms.

[0017] [2]

[0018] As a lens resin composition described in [1] above,

[0019] A resin composition for lenses, wherein the above epoxy compound (Y) is represented by the general formula (2).

[0020] [Chemical Formula 2]

[0021]

[0022] (In the general formula (2),

[0023] R 5 , R 6 , R 8 and R 9 Each independently represents a hydrogen atom, a C1- to C4 alkyl group, or a trifluoromethyl group, and

[0024] R 7 It represents a hydrogen atom or a glycidyl group,

[0025] n is the average number of iterations and represents a real number in the range of 0 to 30.

[0026] [3]

[0027] As a resin composition for lenses described in [1] or [2] above,

[0028] A resin composition for lenses, wherein the epoxy equivalent of the above epoxy compound (Y) is 100 g / eq or more and 200 g / eq or less.

[0029] [4]

[0030] A resin composition for a lens described in any one of [1] to [3] above,

[0031] A lens resin composition having a content of 40 mass% or more of the non-volatile components of the lens resin composition, wherein the epoxy compound (Y) is present in the above composition.

[0032] [5]

[0033] A resin composition for a lens described in any one of [1] to [4] above,

[0034] A resin composition for a lens, wherein the above photocation polymerization initiator (X) comprises an anion represented by either formula (3) or (4) as an anion.

[0035] [Chemical Formula 3]

[0036]

[0037] [Chemical Formula 4]

[0038]

[0039] [6]

[0040] A resin composition for a lens described in any one of [1] to [5] above,

[0041] A resin composition for lenses in which the above photocationic polymerization initiator (X) comprises a sulfonium ion as a cation.

[0042] [7]

[0043] A resin composition for lenses described in any one of [1] to [6] above,

[0044] A resin composition for lenses further comprising a single-acting epoxy compound (Z) represented by the general formula (5).

[0045] [Chemical Formula 5]

[0046]

[0047] (In general formula (5), A is selected from single bonds, oxygen atoms, and sulfur atoms, and R 10 is an alkylene having 1 to 8 carbon atoms, and any methylene group may be substituted with an oxygen atom.

[0048] [8]

[0049] As a lens resin composition described in [7] above,

[0050] A lens resin composition in which the above-mentioned single-acting epoxy compound (Z) is o-phenylphenol glycidyl ether.

[0051] [9]

[0052] A resin composition for a lens described in any one of [1] to [8] above,

[0053] A resin composition for lenses further comprising an oxetane compound (W).

[0054]

[10]

[0055] A resin composition for a lens described in any one of [1] to [9] above,

[0056] A resin composition for lenses, wherein the above oxetane compound (W) is a biphenyl-type oxetane compound.

[0057]

[11]

[0058] A resin composition for a lens described in any one of [1] to

[10] above,

[0059] A lens resin composition having a viscosity of 100 mPa·s or more and 5000 mPa·s or less when the lens resin composition is measured with an E-type viscometer under conditions of a temperature of 25°C and a rotation speed of 2.5 rpm.

[0060]

[12]

[0061] A resin composition for a lens described in any one of [1] to

[11] above,

[0062] The resin composition for the lens is coated on a glass plate to a thickness of 250 μm, with a wavelength of 365 nm, an irradiation intensity of 150 mW / cm², and an integrated irradiation dose of 3000 mJ / cm². 2 A resin composition for lenses, wherein a cured product obtained by UV exposure under conditions and heating under a nitrogen atmosphere at 120°C for 30 minutes satisfies the requirements of (A) to (D) below.

[0063] (A) The curing shrinkage rate of the cured product is 1.0% or more and 5.0% or less.

[0064] (B) The refractive index of the cured material is 1.57 or higher.

[0065] (C) The light transmittance in the thickness direction of the cured material is 80% or more.

[0066] (D) The rate of change in light transmittance in the thickness direction of the cured product after heating (125°C for 168 hours) is 10% or less.

[0067]

[13]

[0068] A resin composition for a lens described in any one of [1] to

[12] above,

[0069] A lens resin composition used in wafer-level lenses.

[0070]

[14]

[0071] A cured lens product obtained by curing a lens resin composition described in any one of [1] to

[13] above.

[0072]

[15]

[0073] A lens having a cured lens material as described in

[14] above. Effects of the invention

[0074] The resin composition for lenses of the present invention, by having the above composition, can form a cured product having low curing shrinkage rate, high refractive index, high light transmittance, and high heat resistance.

[0075] In addition, since the cured lens product of the present invention is obtained by curing the lens resin composition, it possesses low curing shrinkage, high refractive index, high light transmittance, and high heat resistance.

[0076] Furthermore, since the lens of the present invention has a structure in which the lens curing material is laminated, it possesses low curing shrinkage rate, high refractive index, high light transmittance, and high heat resistance. Brief explanation of the drawing

[0077] FIG. 1 is a plan view showing an example of the configuration of a wafer-level lens array having a plurality of wafer-level lenses. Specific details for implementing the invention

[0078] The present invention will be explained below based on embodiments.

[0079] In this embodiment, "A to B" indicating a numerical range indicates A or greater and B or less unless otherwise specified.

[0080] In the present embodiment, the term “having a substituent” for a group such as an alkyl group means that, unless specifically mentioned otherwise, a hydrogen atom present in the structure is substituted with a substituent. The position and number of substituents are not specifically limited. On the other hand, when a substituent has a carbon atom, the number of carbon atoms of the substituent is not included in the number of carbon atoms of the group having the substituent. For example, in the case of an ethyl group having a phenyl group as a substituent, it is considered as an alkyl group having two carbon atoms.

[0081] The non-volatile component in this embodiment is a component of the lens resin composition excluding volatile components such as solvents.

[0082] [Resin composition for lenses]

[0083] The lens resin composition according to the present embodiment comprises a photocationic polymerization initiator (X) comprising a salt formed from an anion represented by the general formula (1) and a cation, and an epoxy compound (Y) comprising two or more epoxy groups in the molecule.

[0084] [Chemical Formula 6]

[0085]

[0086] In the general formula (1), R 1 ~R 4 Each independently represents an alkyl group having 1 to 18 carbon atoms or an aryl group having 6 to 14 carbon atoms.

[0087] With the lens resin composition according to the present embodiment, a cured product having low curing shrinkage, high refractive index, high light transmittance, and high heat resistance can be formed. Although the detailed mechanism is not clear, it is presumed that the photocationic polymerization initiator containing anionic gallium suppresses degradation caused by heating, such as discoloration, because it hardly generates strong acid components even when heated. In addition, the photocationic polymerization initiator containing anionic gallium can suppress adverse effects on performance such as curing shrinkage, refractive index, and light transmittance while exhibiting polymerization performance at the level of conventional technology.

[0088] Hereinafter, each component contained in the lens resin composition according to the present embodiment will be described in detail.

[0089] <Photocationic Polymerization Initiator(X)>

[0090] The resin composition for lenses according to the present embodiment comprises a photocationic polymerization initiator (X) comprising an anion represented by the general formula (1) and a salt formed from a cation.

[0091] [Chemical Formula 7]

[0092]

[0093] In the general formula (1), R 1 ~R 4 Each independently represents an alkyl group having 1 to 18 carbon atoms or an aryl group having 6 to 14 carbon atoms.

[0094] R of general formula (1) 1 ~R 4 The alkyl group having 1 to 18 carbon atoms represented by is not limited to straight chain, branched chain, or cyclic forms.

[0095] Specific examples include alkyl groups such as methyl, ethyl, propyl, isopropyl, n-butyl, t-butyl, hexyl, octyl, 2-ethylhexyl, or decyl groups; cycloalkyl groups such as cyclopentyl, cyclohexyl, cyclooctyl, norvonyl, bicyclononyl, or tricyclodecane groups; etc.

[0096] R of general formula (1) 1 ~R 4 Specific examples of the aryl group having 6 to 14 carbon atoms represented by the phenyl group, tolyl group, naphthyl group, biphenyl group, terphenyl group, phenanthryl group, or anthraceneyl group may be exemplified.

[0097] R of general formula (1) 1 ~R 4 The alkyl group having 1 to 18 carbon atoms or the aryl group having 6 to 14 carbon atoms represented by may have a substituent.

[0098] R of general formula (1) 1 ~R 4 The substituents that may be present in the alkyl group having 1 to 18 carbon atoms or the aryl group having 6 to 14 carbon atoms represented by are not particularly limited. Examples include halogen atoms, hydrocarbon groups, halogen-containing groups, oxygen-containing groups, sulfur-containing groups, and nitrogen-containing groups.

[0099] Examples of halogen atoms include fluorine atoms, chlorine atoms, or bromine atoms.

[0100] As hydrocarbon groups, alkyl groups such as methyl, ethyl, propyl, isopropyl, n-butyl, t-butyl, hexyl, octyl, 2-ethylhexyl, or decyl groups; cycloalkyl groups such as cyclopentyl, cyclohexyl, cyclooctyl, norbornyl, bicyclononyl, or tricyclodecane groups; aryl groups such as phenyl, tolyl, naphthyl, biphenyl, terphenyl, phenanthryl, or anthraceneyl groups; and aralkyl groups such as benzyl or phenylethyl groups; Examples include diene-based divalent derivatives such as 1,3-butadieneyl group, isopreneyl(2-methyl-1,3-butadieneyl) group, piperylenyl(1,3-pentadieneyl) group, 2,4-hexadieneyl group, 1,4-diphenyl-1,3-pentadieneyl group or cyclopentadieneyl group.

[0101] R 1 ~R 4 Examples of halogen-containing groups that may be possessed by the alkyl group having 1 to 18 carbon atoms shown include halogen-containing hydrocarbon groups such as trifluoromethyl, pentafluoroethyl, 1,1,1,3,3,3-hexafluoro-2-propyl or nonafluoro-t-butyl; halogen-containing aryl groups such as pentafluorophenyl, pentachlorophenyl; etc.

[0102] Examples of oxygen-containing groups include alkoxy groups such as methoxy groups, ethoxy groups, n-propoxy groups, isopropoxy groups, n-butoxy groups, isobutoxy groups, or t-butoxy groups; aryloxy groups such as phenoxy groups, 2,6-dimethylphenoxy groups, or 2,4,6-trimethylphenoxy groups; ester groups such as acetyloxy groups, benzoyloxy groups, methoxycarbonyl groups, phenoxycarbonyl groups, or p-chlorophenoxycarbonyl groups; ether groups; acyl groups such as formyl groups, acetyl groups, benzoyl groups, p-chlorobenzoyl groups, or p-methoxybenzoyl groups; carboxyl groups; carbonator groups; hydroxyl groups; peroxy groups; carboxylic acid anhydrides; furyl groups; etc.

[0103] As sulfur-containing groups, mercapto group; thioester groups such as acetylthio group, benzoylthio group, methylthiocarbonyl group, or phenylthiocarbonyl group; dithioester group; alkylthio group such as methylthio group or ethylthio group; arylthio group such as phenylthio group, methylphenylthio group, or naphthylthio group; thioacyl group; thioether group; thiocyanate ester group; isothiocyanate ester group; sulfonic acid ester groups such as methyl sulfonate group, ethyl sulfonate group, or phenyl sulfonate group; sulfonamide groups such as phenylsulfonamide group, N-methylsulfonamide group, or N-methyl-p-toluenesulfonamide group; thiocarboxyl group; dithiocarboxyl group; sulfo group; sulfonyl group; Examples include Sulpin Diary; Sulpen Diary; etc.

[0104] Examples of nitrogen-containing groups include: an amino group; an alkylamino group such as a dimethylamino group or an ethylmethylamino group; an arylamino group such as a diphenylamino group; an imino group; an alkylimino group such as a methylimino group, an ethylimino group, a propylimino group, or a butylimino group; an arylimino group such as a phenylimino group; an amide group; an alkylamide group such as an acetamide group or an N-methylacetamide group; an arylamide group such as an N-methylbenzamide group; an imide group; an alkylimide group such as an acetimide group; an arylimide group such as a benzimide group; a pyrrolidino group; a hydrazino group; a hydrazono group; a nitro group; a nitroso group; a cyano group; an isocyano group; a cyanic acid ester group; an amidino group; a diazo group; an amino group; etc.

[0105] R 1 ~R 4 It is preferable that at least three of them are aryl groups having 6 to 14 carbon atoms, and R 1 ~R 4 It is more desirable that all of them are aryl groups having 6 to 14 carbon atoms.

[0106] R 1 ~R 4It is preferable that the photocation polymerization initiator (X) has a halogen atom as a substituent, and it is more preferable that it has a fluorine atom as a substituent. Specifically, it is particularly preferable that the photocation polymerization initiator (X) includes an anion represented by either formula (3) or (4) as an anion. By doing so, the heat resistance of the lens cured body formed from the lens resin composition can be further improved.

[0107] [Chemical Formula 8]

[0108]

[0109] [Chemical Formula 9]

[0110]

[0111] The photocationic polymerization initiator (X) includes an anion represented by the general formula (1) and a cation that forms a salt.

[0112] The cation that forms the salt with the anion represented by the general formula (1) is not particularly limited as long as it is a monovalent cation. For example, oxonium ions, ammonium ions, phosphonium ions, sulfonium ions, or iodonium ions can be examples.

[0113] As oxonium ions, oxonium such as trimethyloxonium, diethylmethyloxonium, triethyloxonium, and tetramethylenemethyloxonium; pyrillinium such as 4-methylpyrillinium, 2,4,6-trimethylpyrillinium, 2,6-di-tert-butylpyrillinium, and 2,6-diphenylpyrillinium; chromenium such as 2,4-dimethylchromenium and 1,3-dimethylisochromenium; isochromenium;

[0114] Examples of the back can be given.

[0115] As ammonium ions, pyrrolidinium such as N,N-dimethylpyrrolidinium, N-ethyl-N-methylpyrrolidinium, and N,N-diethylpyrrolidinium; imidazolinium such as N,N'-dimethylimidazolinium, N,N'-diethylimidazolinium, N-ethyl-N'-methylimidazolinium, 1,3,4-trimethylimidazolinium, and 1,2,3,4-tetramethylimidazolinium; tetrahydropyrimidinium such as N,N'-dimethyltetrahydropyrimidinium; morpholinium such as N,N'-dimethylmorpholinium; piperidinium such as N,N'-diethylpiperidinium; pyridinium such as N-methylpyridinium, N-benzylpyridinium, and N-phenasilpyridium; Examples include imidazolium such as N,N'-dimethylimidazolium; quinolium such as N-methylquinolium, N-benzylquinolium, and N-phenacylquinolium; isoquinolium such as N-methylisoquinolium; thiazonium such as benzylbenzothiazonium and phenacylbenzothiazonium; and acridinium such as benzylacridinium and phenacylacridinium.

[0116] Examples of phosphonium ions include tetraarylphosphonium such as tetraphenylphosphonium, tetra-p-tolylphosphonium, tetrakis(2-methoxyphenyl)phosphonium, tetrakis(3-methoxyphenyl)phosphonium, and tetrakis(4-methoxyphenyl)phosphonium; triarylphosphonium such as triphenylbenzylphosphonium, triphenylphenacylphosphonium, triphenylmethylphosphonium, and triphenylbutylphosphonium; tetraalkylphosphonium such as triethylbenzylphosphonium, tributylbenzylphosphonium, tetraethylphosphonium, tetrabutylphosphonium, tetrahexylphosphonium, triethylphenacylphosphonium, and tributylphenacylphosphonium; etc.

[0117] As sulfonium ions, triphenylsulfonium, tri-p-tolylsulfonium, tri-o-tolylsulfonium, tris(4-methoxyphenyl)sulfonium, 1-naphthyldiphenylsulfonium, 2-naphthyldiphenylsulfonium, tris(4-fluorophenyl)sulfonium, tri-1-naphthylsulfonium, tri-2-naphthylsulfonium, tris(4-hydroxyphenyl)sulfonium, 4-(phenylthio)phenyldiphenylsulfonium, 4-(p-tolylthio)phenyldi-p-tolylsulfonium, 4-(4-methoxyphenylthio)phenylbis(4-methoxyphenyl)sulfonium, 4-(phenylthio)phenylbis(4-fluorophenyl)sulfonium, 4-(phenylthio)phenylbis(4-methoxyphenyl)sulfonium, 4-(phenylthio)phenyldi-p-tolylsulfonium, [4-(4-biphenylylthio)phenyl]-4-biphenylylphenylsulfonium, [4-(2-thioxantonylthio)phenyl]diphenylsulfonium, bis[4-(diphenylsulfonio)phenyl]sulfide, bis[4-{bis[4-(2-hydroxyethoxy)phenyl]sulfonio}phenyl]sulfide, bis{4-[bis(4-fluorophenyl)sulfonio]phenyl}sulfide, bis{4-[bis(4-methylphenyl)sulfonio]phenyl}sulfide, bis{4-[bis(4-methoxyphenyl)sulfonio]phenyl}sulfide, 4-(4-benzoyl-2-chlorophenylthio)phenylbis(4-fluorophenyl)sulfonium, 4-(4-benzoyl-2-chlorophenylthio)phenyldiphenylsulfonium, 4-(4-benzoylphenylthio)phenylbis(4-fluorophenyl)sulfonium, 4-(4-benzoylphenylthio)phenyldiphenylsulfonium, 7-isopropyl-9-oxo-10-thia-9,10-dihydroanthracene-2-yldi-p-tolylsulfonium, 7-isopropyl-9-oxo-10-thia-9,10-dihydroanthracene-2-yldiphenylsulfonium, 2-[(di-p-tolyl)sulfonio]thioxantone, 2-[(diphenyl)sulfonio]thioxantone, 4-(9-oxo-9H-thioxanthen-2-yl)thiophenyl-9-oxo-9H-thioxanthen-2-ylphenylsulfonium, 4-[4-(4-tert-butylbenzoyl)phenylthio]phenyldi-p-tolylsulfonium, 4-[4-(4-tert-butylbenzoyl)phenylthio]phenyldiphenylsulfonium, 4-[4-(benzoylphenylthio)]phenyldi-p-tolylsulfonium, 4-[4-(benzoylphenylthio)]phenyldiphenylsulfonium,Triarylsulfoniums such as 5-(4-methoxyphenyl)thioantrenium, 5-phenylthioantrenium, 5-tolylthioantrenium, 5-(4-ethoxyphenyl)thioantrenium, and 5-(2,4,6-trimethylphenyl)thioantrenium; diarylsulfoniums such as diphenylphenacylsulfonium, diphenyl 4-nitropenasylsulfonium, diphenylbenzylsulfonium, and diphenylmethylsulfonium; Monoaryl sulfons such as phenylmethylbenzylsulfonium, 4-hydroxyphenylmethylbenzylsulfonium, 4-methoxyphenylmethylbenzylsulfonium, 4-acetocarbonyloxyphenylmethylbenzylsulfonium, 4-hydroxyphenyl(2-naphthylmethyl)methylsulfonium, 2-naphthylmethylbenzylsulfonium, 2-naphthylmethyl(1-ethoxycarbonyl)ethylsulfonium, phenylmethylphenacylsulfonium, 4-hydroxyphenylmethylphenacylsulfonium, 4-methoxyphenylmethylphenacylsulfonium, 4-acetocarbonyloxyphenylmethylphenacylsulfonium, 2-naphthylmethylphenacylsulfonium, 2-naphthyloctadecylphenacylsulfonium, and 9-anthracenylmethylphenacylsulfonium; Examples of trialkylsulfoniums include dimethylphenacylsulfonium, phenacyltetrahydrothiophenium, dimethylbenzylsulfonium, benzyltetrahydrothiophenium, and octadecylmethylphenacylsulfonium.

[0118] Examples of iodium ions include diphenyliodonium, di-p-tolyliodonium, bis(4-dodecylphenyl)iodonium, bis(4-methoxyphenyl)iodonium, (4-octyloxyphenyl)phenyliodonium, bis(4-decyloxy)phenyliodonium, 4-(2-hydroxytetradecyloxy)phenylphenyliodonium, 4-isopropylphenyl(p-tolyl)iodonium, and 4-isobutylphenyl(p-tolyl)iodonium.

[0119] The photocationic polymerization initiator (X) preferably comprises, as a cation, an ammonium ion, a phosphonium ion, a sulfonium ion, or an iodonium ion, more preferably comprises a sulfonium ion or an iodonium ion, and more preferably comprises a sulfonium ion.

[0120] The photocationic polymerization initiator (X) preferably contains a salt composed of an anion represented by either formula (3) or (4) and a sulfonium ion. By doing so, the heat resistance of the lens cured body formed from the lens resin composition can be further improved.

[0121] [Chemical Formula 10]

[0122]

[0123] [Chemical Formula 11]

[0124]

[0125] Specific examples of anions contained in the photocationic polymerization initiator (X) are given below, but the anions contained in the photocationic polymerization initiator (X) in this embodiment are not limited to these.

[0126] [Chemical Formula 12]

[0127]

[0128] The photocationic polymerization initiator (X) can be synthesized in accordance with known methods, for example, as described in International Publication No. 2018 / 020974. Alternatively, commercially available products such as CPI-310FG (trade name, photocationic polymerization initiator, acid aprosate) may be obtained and used.

[0129] The content of the photocationic polymerization initiator (X) is preferably 0.05 to 15 parts by mass, more preferably 0.07 to 10 parts by mass, even more preferably 0.1 to 8 parts by mass, and most preferably 0.5 to 5 parts by mass, based on 100 parts by mass of the epoxy compound (Y).

[0130] The photocationic polymerization initiator (X) may be used as a single type or as a mixture of multiple types. When using a mixture of multiple types, the sum of the contents of each photocationic polymerization initiator (X) shall be the content of the photocationic polymerization initiator (X).

[0131] Meanwhile, if the molar extinction coefficient of the photocationic polymerization initiator (X) at a wavelength of 300 to 380 nm is high, the content may be adjusted to an appropriate amount depending on the volume or thickness when using the lens resin composition.

[0132] <Epoxy Compound (Y)>

[0133] The lens resin composition according to the present embodiment comprises an epoxy compound (Y) containing two or more epoxy groups within the molecule.

[0134] Examples of epoxy compounds (Y) containing two or more epoxy groups within a molecule include diethylene glycol diglycidyl ether, hexanediol diglycidyl ether, dimethylolpropane diglycidyl ether, polypropylene glycol diglycidyl ether, trimethylolpropane triglycidyl ether, trimethylolpropane triglycidyl ether, and pentaerythritol tetraglycidyl ether.

[0135] In addition, examples of epoxy compounds (Y) containing two or more epoxy groups within a molecule include alicyclic epoxy resins such as 3',4'-epoxycyclohexylmethyl-3,4-epoxycyclohexane carboxylate and ε-caprolactone modified 3',4'-epoxycyclohexylmethyl-3,4-epoxycyclohexane carboxylate.

[0136] Furthermore, examples of epoxy compounds (Y) containing two or more epoxy groups within a molecule include bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, biphenyl-phenol novolak type epoxy compounds, and epoxy compounds having aromatic rings in which some or all of the alcoholic hydroxyl groups in the structure of these epoxy compounds are epoxidized.

[0137] Examples of commercially available epoxy compounds (Y) include the EPICLON series represented by EXA-850CRP (Bisphenol A type epoxy resin, manufactured by DIC Corporation), the jER series represented by jER828 (manufactured by Mitsubishi Chemical Corporation), the YD series represented by YD-127 (manufactured by Nittetsu Chemical & Material Corporation), and TECHMORE VG3101L (Tri-function epoxy resin, manufactured by Printech Corporation).

[0138] It is preferable that the epoxy compound (Y) be an epoxy compound having an aromatic ring. By doing so, the refractive index of the cured product formed by curing the lens resin composition can be increased, thereby improving the optical properties of the lens.

[0139] It is more preferable that the epoxy compound (Y) be represented by the general formula (2).

[0140] [Chemical Formula 13]

[0141]

[0142] In the general formula (2),

[0143] R 5 , R 6 , R 8 and R 9 Each independently represents a hydrogen atom, a C1- to C4 alkyl group, or a trifluoromethyl group, and

[0144] R 7 It represents a hydrogen atom or a glycidyl group,

[0145] n is the average number of repetitions and represents a real number in the range of 0 to 30.

[0146] R 5 , R 6 , R 8 and R 9 As the alkyl group having 1 to 4 carbon atoms represented by, R 1 ~R 4 Among the alkyl groups having 1 to 18 carbon atoms represented by, those having 1 to 4 carbon atoms can be exemplified.

[0147] R 5 , R 6 , R 8 and R 9 It is preferable that it be an alkyl group having 1 to 4 carbon atoms or a trifluoromethyl group, more preferable that it be a methyl group or a trifluoromethyl group, and even more preferable that it be a methyl group.

[0148] It is preferable that n be 1 to 20, and more preferable that n be 5 to 15. Meanwhile, n is calculated from the value of the weight-average molecular weight calculated as a polystyrene equivalent based on the measurement results of GPC (gel permeation chromatography).

[0149] There is no particular limit to the epoxy equivalent of the epoxy compound (Y), but preferably it is 100 g / eq or more and 200 g / eq or less, and more preferably 120 g / eq or more and 180 g / eq or less. Meanwhile, the epoxy equivalent in this specification is a value measured by a method in accordance with JIS K7236.

[0150] The content of the epoxy compound (Y) in the non-volatile component of the lens resin composition of the present embodiment is preferably 40 mass% or more, more preferably 50 mass% or more, and even more preferably 70 mass% or more.

[0151] There is no particular upper limit on the content of the epoxy compound (Y) in the non-volatile component of the lens resin composition of the present embodiment, but it is typically 99 mass% or less.

[0152] The epoxy compound (Y) may be used as a single type or as a mixture of multiple types. When using a mixture of multiple types, the sum of the contents of each epoxy compound (Y) shall be the content of the epoxy compound (Y).

[0153] <Other ingredients>

[0154] The lens resin composition according to the present embodiment may, if necessary, contain a monofunctional epoxy compound (Z), an oxetane compound (W), a solvent, an adhesive agent, a polyol compound, a polyhydric phenol compound, a sensitizer, an ion catcher, a photocation polymerization initiator other than the photocation polymerization initiator (X) (other photocation polymerization initiators), etc.

[0155] (Single-acting epoxy compound (Z))

[0156] The resin composition for lenses according to the present embodiment preferably further includes a monofunctional epoxy compound (Z) represented by the general formula (5).

[0157] By this, the heat resistance of the cured lens body formed from the lens resin composition can be further improved. In addition, the glass adhesion of the lens resin composition can be improved.

[0158] [Chemical Formula 14]

[0159]

[0160] In the general formula (5), A is selected from single bonds, oxygen atoms, and sulfur atoms, and R 10 It is an alkylene having 1 to 8 carbon atoms, and any methylene group may be substituted with an oxygen atom.

[0161] R 10 It is preferable that it be an alkylene having 1 to 4 carbon atoms, and more preferable that it be an alkylene having 1 to 2 carbon atoms.

[0162] R 10 It is preferable that any methylene group be replaced by an oxygen atom.

[0163] The single-acting epoxy compound (Z) is preferably o-phenylphenol glycidyl ether.

[0164] Examples of commercially available single-function epoxy compounds (Z) include OPP-EP (o-phenylphenol glycidyl ether, manufactured by Yokkaichi Synthetic Co., Ltd.) and OPP-G (o-phenylphenol glycidyl ether, manufactured by Sanko Co., Ltd.).

[0165] When the lens resin composition of the present embodiment contains a monofunctional epoxy compound (Z), the content thereof is preferably 1 mass% or more, more preferably 5 mass% or more, and even more preferably 10 mass% or more among the non-volatile components of the lens resin composition of the present embodiment.

[0166] When the lens resin composition of the present embodiment contains a monofunctional epoxy compound (Z), the content thereof is preferably 70 mass% or less, more preferably 60 mass% or less, and even more preferably 50 mass% or less among the non-volatile components of the lens resin composition of the present embodiment.

[0167] When the lens resin composition of the present embodiment contains a single-acting epoxy compound (Z), the content is preferably 1 part by mass or more, more preferably 5 parts by mass or more, and even more preferably 10 parts by mass or more, with respect to 100 parts by mass of the epoxy compound (Y).

[0168] When the resin composition for the lens of the present embodiment contains a single-acting epoxy compound (Z), the content thereof is, for example, 200 parts by mass or less, preferably 150 parts by mass or less, more preferably 100 parts by mass or less, even more preferably 80 parts by mass or less, even more preferably 60 parts by mass or less, even more preferably 40 parts by mass or less, and even more preferably 25 parts by mass or less, with respect to 100 parts by mass of the epoxy compound (Y).

[0169] The single-function epoxy compound (Z) may be used as a single type or as a mixture of multiple types. When multiple types are mixed, the sum of the contents of each single-function epoxy compound (Z) is considered the content of the single-function epoxy compound (Z).

[0170] (Oxetane compound)

[0171] The resin composition for lenses according to the present embodiment preferably further comprises an oxetane compound (W).

[0172] By this, the heat resistance of the cured lens body formed from the lens resin composition can be further improved. In addition, the glass adhesion of the lens resin composition can be improved. Furthermore, the curability of the resin composition can be improved.

[0173] The oxetane compound (W) is not particularly limited and generally known ones may be used. Specific examples of oxetane resins include, for example, oxetane, 2-methyl oxetane, 3-methyl oxetane, 2,2-dimethyl oxetane, 3,3-dimethyl oxetane, 3-ethyl-3-hydroxymethyl oxetane, and biphenyl-type oxetane.

[0174] Oxetane compound (W) may be used as a single type or as a mixture of multiple types. When multiple types are mixed, the sum of the contents of each oxetane compound (W) is considered the content of the oxetane compound (W).

[0175] The oxetane compound (W) is preferably a biphenyl-type oxetane compound. Specific examples of biphenyl-type oxetane include, for instance, xylylene bis-oxetane.

[0176] Examples of commercially available oxetane compounds (W) include Aaron Oxetane OXT-101 (3-ethyl-3-hydroxymethyl oxetane, manufactured by Doa Synthetic Co., Ltd.) and Aaron Oxetane OXT-121 (xylylene bis-oxetane, manufactured by Doa Synthetic Co., Ltd.).

[0177] When the lens resin composition of the present embodiment contains an oxetane compound (W), the content thereof is preferably 0.01 mass% or more, more preferably 0.1 mass% or more, even more preferably 1 mass% or more, and even more preferably 2 mass% or more among the non-volatile components of the lens resin composition of the present embodiment, in order to improve glass adhesion, heat resistance and curability.

[0178] When the resin composition for the lens of the present embodiment contains an oxetane compound (W), the content is preferably 50 mass% or less, more preferably 40 mass% or less, even more preferably 30 mass% or less, even more preferably 20 mass% or less, and even more preferably 10 mass% or less.

[0179] When the lens resin composition of the present embodiment contains oxetane resin (W), the content is preferably 1 part by mass or more, more preferably 5 parts by mass or more, and even more preferably 10 parts by mass or more, with respect to 100 parts by mass of epoxy compound (Y).

[0180] When the lens resin composition of the present embodiment contains oxetane resin (W), the content is, for example, 200 parts by mass or less, preferably 150 parts by mass or less, more preferably 100 parts by mass or less, even more preferably 80 parts by mass or less, even more preferably 60 parts by mass or less, even more preferably 40 parts by mass or less, even more preferably 25 parts by mass or less, and even more preferably 15 parts by mass or less.

[0181] (solvent)

[0182] The solvent contained in the lens resin composition according to the present embodiment is not particularly limited, but is preferably used to be capable of dissolving each component of the lens resin composition. Such organic solvents include ketones such as acetone, ethyl methyl ketone, methyl isobutyl ketone, cyclohexanone, and cyclopentanone; aromatic hydrocarbons such as toluene, xylene, methoxybenzene, and tetramethylbenzene; and glycol ethers such as diglyme, dipropylene glycol dimethyl ether, and dipropylene glycol diethyl ether. Esters such as ethyl lactate, butyl lactate, propyl lactate, ethyl acetate, methyl acetacetate, ethyl acetacetate, methyl propionate, ethyl propionate, propyl propionate, isopropyl propionate, 2-methyl hydroxypropionate, 2-ethyl hydroxypropionate, methyl-3-methoxypropionate, ethyl-3-methoxypropionate, ethyl-3-ethoxypropionate, propyl-3-methoxypropionate, butyl acetate, butyl cellosolve acetate, carbitol acetate, and propylene glycol monomethyl ether acetate; lactones such as α-acetolactone, β-propiolactone, γ-butyrolactone, and δ-valerolactone; Examples include alcohols such as methanol, ethanol, cellosolve, and methyl cellosolve; aliphatic hydrocarbons such as octane and decane; and petroleum-based solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha.

[0183] When the resin composition for lenses of the present embodiment contains a solvent, the content is not particularly limited as long as it is within a range that does not impair the effects of the present invention, and is typically 95 mass% or less, preferably 10 to 90 mass%.

[0184] A solvent may be used as a single type or as a mixture of multiple types. In the case of using a mixture of multiple types, the sum of the contents of each solvent shall be considered the total solvent content.

[0185] When the epoxy compound (Y) is in a liquid state at room temperature, coating, etc. can be performed appropriately even without adding a solvent or substantially without adding a solvent.

[0186] (Adhesion enhancer)

[0187] The adhesion-imparting agent contained in the lens resin composition according to the present embodiment is not particularly limited and known silane coupling agents or titanium coupling agents, etc., may be used. It is preferable to use a silane coupling agent from the perspective of improving glass adhesion.

[0188] Examples of silane coupling agents include 3-chloropropyltrimethoxysilane, vinyltrichlorosilane, vinyltriethoxysilane, vinyltrimethoxysilane, vinyltris(2-methoxyethoxy)silane, 3-methacryloxypropyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-mercaptopropyltrimethoxysilane, 8-glycidyloctyltrimethoxysilane, etc.

[0189] When the resin composition for lenses of the present embodiment contains an adhesive agent, the content is not particularly limited as long as it is within a range that does not impair the effects of the present invention, and is preferably 15 mass% or less, more preferably 10 mass% or less, even more preferably 5 mass% or less, and even more preferably 2 mass% or less among the non-volatile components of the resin composition for lenses of the present embodiment.

[0190] When the resin composition for lenses of the present embodiment contains an adhesive agent, the content is not particularly limited as long as it is within a range that does not impair the effects of the present invention, and is preferably 0.1 mass% or more, more preferably 0.5 mass% or more, and even more preferably 0.8 mass% or more among the non-volatile components of the resin composition for lenses of the present embodiment.

[0191] Adhesion promoters may be used as a single type or as a mixture of multiple types. In the case of using a mixture of multiple types, the sum of the contents of each adhesion promoter shall be considered as the content of the adhesion promoter.

[0192] (Polyol compounds)

[0193] The polyol compound contained in the lens resin composition according to the present embodiment is not particularly limited, but is typically a polyester polyol-based compound containing a hydroxyl group that reacts with an epoxy group under the influence of a strong acid catalyst. For example, the polyol compound disclosed in Japanese Patent Publication No. 5901070 may be used.

[0194] When the lens resin composition of the present embodiment contains a polyol compound, the content is not particularly limited as long as it is within a range that does not impair the effects of the present invention, and is typically 1 to 30 parts by mass, preferably 2 to 25 parts by mass, with respect to 100 parts by mass of epoxy compound (Y).

[0195] Polyol compounds may be used as a single type or as a mixture of multiple types. When multiple types are mixed, the sum of the contents of each polyol compound is considered the polyol compound content.

[0196] The polyvalent phenolic compound contained in the lens resin composition according to the present embodiment is a compound capable of curing the crosslinking density of the epoxy compound to a high degree by heating. For example, the polyvalent phenolic compound disclosed in Japanese Patent Publication No. 5967824 may be used.

[0197] (Polyvalent phenol compounds)

[0198] When the resin composition for lenses of the present embodiment contains a polyphenol compound, the content is not particularly limited as long as it is within a range that does not impair the effects of the present invention, and is typically 3 to 40 parts by mass, preferably 4 to 30 parts by mass, more preferably 5 to 25 parts by mass, with respect to 100 parts by mass of epoxy compound (Y).

[0199] Polyvalent phenol compounds may be used as a single type or as a mixture of multiple types. In the case of using a mixture of multiple types, the sum of the contents of each polyvalent phenol compound is considered as the content of the polyvalent phenol compound.

[0200] (Increase / Decrease System)

[0201] The sensitizer contained in the lens resin composition according to the present embodiment serves to donate absorbed light energy to a photocationic polymerization initiator. Examples include thioxantones, anthracene compounds having alkoxy groups at the 9th and 10th positions (9,10-dialkoxyanthracene derivatives).

[0202] When the resin composition for the lens of the present embodiment contains a sensitizer, the content is not particularly limited as long as it is within a range that does not impair the effects of the present invention, and is preferably 30 parts by mass or less, more preferably 20 parts by mass or less, with respect to 100 parts by mass of photocationic polymerization initiator (X).

[0203] When the resin composition for the lens of the present embodiment contains a sensitizer, the content is not particularly limited as long as it is within a range that does not impair the effects of the present invention, and is typically 0.1 parts by mass or more per 100 parts by mass of photocationic polymerization initiator (X).

[0204] A sensitizer may be used as a single type or as a mixture of multiple types. In the case of using a mixture of multiple types, the sum of the contents of each sensitizer shall be considered as the content of the sensitizer.

[0205] (Ion catcher)

[0206] The ion catcher contained in the lens resin composition according to the present embodiment can reduce adverse effects caused by ions derived from the photocationic polymerization initiator (X). For example, organoaluminum compounds or onium weak acid salt compounds that emit a weak acid upon ultraviolet irradiation can be used as ion catchers.

[0207] When the resin composition for lenses of the present embodiment contains an ion catcher, the content thereof is not particularly limited as long as it is within a range that does not impair the effects of the present invention. In the case of organoaluminum compounds, it is preferably 0.1 to 10 parts by mass per 100 parts by mass of photocationic polymerization initiator (X). In the case of onium weak salt compounds, it is preferably 0.001 to 2 parts by mass per 100 parts by mass of photocationic polymerization initiator (X).

[0208] An ion catcher may be used as a single type or as a mixture of multiple types. In the case of using a mixture of multiple types, the sum of the contents of each ion catcher shall be the total ion catcher content.

[0209] (Other photocationic polymerization initiators)

[0210] The resin composition for lenses according to the present embodiment may contain a photocation polymerization initiator other than the photocation polymerization initiator (X) (other photocation polymerization initiators).

[0211] Other photocation polymerization initiators contained in the lens resin composition according to the present embodiment are not particularly limited and known ones may be used.

[0212] Other photocationic polymerization initiators include [(R 20 ) s B(Phf) 4-s ] - (during food, R 20represents a phenyl group or a biphenylyl group. Phf represents a phenyl group in which at least one hydrogen atom is substituted with at least one selected from perfluoroalkyl groups, perfluoroalkoxy groups, and halogen atoms. s is an integer from 0 to 3), BF4 - , [(Rf) n PF 6-n ] - (Rf: alkyl group in which 80% or more of the hydrogen atoms are replaced by fluorine atoms, n: integer from 0 to 5), AsF6 - , SbF6 - Examples of agents having pentafluorohydroxyantimonate, etc. as anions can be given.

[0213] The content of other photocationic polymerization initiators is not particularly limited as long as the effects of the present invention are not impaired, but is preferably 50 parts by mass or less, more preferably 20 parts by mass or less, and even more preferably 10 parts by mass or less with respect to 100 parts by mass of photocationic polymerization initiator (X).

[0214] Other photocationic polymerization initiators may be used as a single type or as a mixture of multiple types. In the case of using a mixture of multiple types, the sum of the contents of each of the other photocationic polymerization initiators shall be considered as the content of the other photocationic polymerization initiators.

[0215] (Other additives)

[0216] In addition to the above components, the resin composition for lenses of the present embodiment may contain various additives such as antioxidants, light stabilizers, thermoplastic resins, colorants, thickeners, defoaming agents, and leveling agents, as needed.

[0217] The resin composition for lenses according to the present embodiment preferably further includes an antioxidant.

[0218] Examples of antioxidants include phenolic antioxidants, phosphorus-based antioxidants, thioether-based antioxidants, and hindered amine-based antioxidants.

[0219] It is preferable that the antioxidant includes a phenolic antioxidant, and it is more preferable that it includes a hindered phenolic antioxidant.

[0220] Examples of hindered phenolic antioxidants include 2,6-di-t-butylhydroxytoluene and pentaerythritoltetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate].

[0221] Examples of commercially available hindered phenolic antioxidants include AO-20, AO-30, AO-40, AO-50, AO-60, and AO-80 of the ADEKA STARV series manufactured by ADEKA Co., Ltd.

[0222] Examples of phosphorus-based antioxidants include phosphines such as trialkylphosphine and triarylphosphine, trialkyl phosphite and triaryl phosphite.

[0223] Examples of commercially available phosphorus-based antioxidants include the ADEKA STARV series PEP-4C, PEP-8, PEP-24G, PEP-36, HP-10, 260, 522A, 329K, 1178, 1500, 135A, and 3010 manufactured by ADEKA Corporation.

[0224] Examples of commercially available thioether-based antioxidants include AO-26, AO-412S, and AO-503A of the ADEKA STARV series manufactured by ADEKA Corporation.

[0225] Examples of hindered amine-based antioxidants include bis(1,2,2,6,6-pentamethyl-4-piperidinyl)sebacate, methyl(1,2,2,6,6-pentamethyl-4-piperidinyl)sebacate, 2,4-bis[N-butyl-N-(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)amino]-6-(2-hydroxyethylamine)-1,3,5-triazine, decaneate bis(2,2,6,6-tetramethyl-1-(octyloxy)-4-piperidinyl)ester, and sebacate bis(1,2,2,6,6-pentamethyl-4-piperidyl).

[0226] Examples of commercially available hindered amine-based antioxidants include AL-72 of the ADEKA STARV series manufactured by ADEKA Corporation, and hindered amine-based antioxidants such as 111FDL, 123, 144, 152, 292, and 5100 of the TINUVIN series manufactured by BASF.

[0227] When using two or more types of antioxidants in combination, the combination of a phenolic antioxidant and a hindered amine-based antioxidant, and the combination of a phenolic antioxidant and a thioether-based antioxidant are preferred.

[0228] When the resin composition for lenses of the present embodiment contains an antioxidant, the content thereof may be appropriately set according to the purpose, but from the viewpoint of obtaining a cured product with less coloration, when the total amount of the epoxy compound (Y), the monofunctional epoxy compound (Z), and the oxetane compound (W) is 100 parts by mass, it is preferably 0.01 parts by mass or more, more preferably 0.1 parts by mass or more, and from the viewpoint of obtaining a resin composition with excellent curability, it is preferably 5 parts by mass or less, more preferably 1 part by mass or less.

[0229] The resin composition for lenses according to the present embodiment preferably further includes a light stabilizer.

[0230] The light stabilizer according to the present embodiment preferably comprises a hindered amine-based light stabilizer. Examples of hindered amine-based light stabilizers include compounds and commercially available products exemplified as hindered amine-based antioxidants, such as bis(1,2,2,6,6-pentamethyl-4-piperidyl) sebacate.

[0231] When the lens resin composition of the present embodiment contains a light stabilizer, the content thereof is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, when the total amount of the epoxy compound (Y), monofunctional epoxy compound (Z), and oxetane compound (W) is 100 parts by mass, and preferably 1 part by mass or less, more preferably 0.5 parts by mass or less.

[0232] <Manufacturing Method>

[0233] The resin composition for lenses according to the present embodiment can be obtained by mixing and stirring each of the above-mentioned components in a conventional manner. Alternatively, if necessary, the components may be dispersed and mixed using a disperser such as a dissolver, a homogenizer, or a three-roll mill. In addition, after mixing, the components may be further filtered using a mesh, a membrane filter, etc.

[0234] <Material Properties>

[0235] The viscosity of the lens resin composition of the present embodiment can be measured, for example, by an E-type viscometer.

[0236] When the viscosity of the lens resin composition of the present embodiment is measured using an E-type viscometer under conditions of a temperature of 25°C and a rotation speed of 2.5 rpm, it is preferably 100 mPa·s or more and 5000 mPa·s or less, more preferably 200 mPa·s or more and 3000 mPa·s or less, and even more preferably 500 mPa·s or more and 2000 mPa·s or less.

[0237] The lens resin composition of the present embodiment is prepared by applying the lens resin composition onto a glass plate to a thickness of 250 μm, with a wavelength of 365 nm, an irradiation intensity of 150 mW / cm², and an integrated irradiation dose of 3000 mJ / cm². 2It is preferable that the curing shrinkage rate of a lens cured product (α) obtained by UV exposure under conditions and heating under a nitrogen atmosphere at 120°C for 30 minutes be 1.0% or more and 5.0% or less, more preferable that it be 1.2% or more and 4.0% or less, and more preferable that it be 1.5% or more and 3.0% or less.

[0238] By having the curing shrinkage rate of the lens cured material (α) within the above range, dimensional accuracy can be improved when manufacturing the lens.

[0239] The curing shrinkage rate of the lens cured material (α) can be obtained by the following procedure.

[0240] First, the specific gravity d1 of the lens resin composition is determined according to JIS Z 8804:2012 (Method for measuring density and specific gravity of liquids). Meanwhile, if the lens resin composition contains volatile components, the specific gravity of the non-volatile components excluding them is determined.

[0241] Next, the specific gravity d2 of the lens cured material (α) is determined according to JIS Z 8807:2012 (Method for measuring density and specific gravity of solids). Using the determined specific gravity value, the curing shrinkage rate is calculated by the following formula.

[0242] Curing shrinkage rate (%) = (1 - d1 / d2) × 100

[0243] In the lens resin composition of the present embodiment, the refractive index of the lens cured product (α) obtained under the above conditions is preferably 1.57 or higher, more preferably 1.58 or higher, and even more preferably 1.59 or higher.

[0244] The optical properties of the lens can be improved by the refractive index of the lens hardened material (α) being in the above range.

[0245] The refractive index of the lens hardened material (α) can be measured by an Abbe refractometer.

[0246] In the lens resin composition of the present embodiment, it is preferable that the light transmittance T1 in the thickness direction of the lens cured product (α) obtained under the above conditions is 80% or more.

[0247] By having the light transmittance of the lens cured material (α) within the above range, a lens with higher transparency can be manufactured.

[0248] The light transmittance T1 in the thickness direction of the lens cured material (α) can be measured at a measurement wavelength of 400 nm by the transmission method using an ultraviolet-visible-near-infrared spectrophotometer.

[0249] In the lens resin composition of the present embodiment, it is preferable that the rate of change in light transmittance in the thickness direction of the lens cured product (α) obtained under the above conditions after heating (125°C for 168 hours) is 10% or less, more preferable that it is 5% or less, and more preferable that it is 2% or less.

[0250] By ensuring that the rate of change in light transmittance after heating of the lens cured material (α) is within the above range, a lens with superior heat resistance can be manufactured.

[0251] The rate of change in light transmittance in the thickness direction of a lens cured material (α) after heating (125°C for 168 hours) can be obtained by the following procedure.

[0252] First, the lens cured material (α) is heated for 168 hours in an oven set to 125°C in an air atmosphere. Then, the light transmittance T2 after heating is obtained by measuring the light transmittance in the thickness direction under the above conditions, and is calculated by the following formula.

[0253] Rate of change in light transmittance after heating (125℃ for 168 hours) (%)

[0254] =(T1-T2) / T1×100

[0255] In the lens resin composition of the present embodiment, it is preferable that the cured product (α) obtained under the above conditions satisfies the requirements of (A) to (D) below.

[0256] (A) The curing shrinkage rate of the cured product is 1.0% or more and 5.0% or less.

[0257] (B) The refractive index of the cured material is 1.57 or higher.

[0258] (C) The light transmittance in the thickness direction of the cured material is 80% or more.

[0259] (D) The rate of change in light transmittance in the thickness direction of the cured product after heating (125°C for 168 hours) is 10% or less.

[0260] By satisfying the requirements of (A) to (D) above, a lens can be manufactured that has dimensional accuracy, optical properties, transparency, and heat resistance.

[0261] <Uses>

[0262] The resin composition for lenses of the present embodiment is suitable for use as a wafer-level lens.

[0263] A wafer-level lens is a lens manufactured by simultaneously creating several lenses from resin on a wafer (wafer-level lens array) and then separating them.

[0264] FIG. 1 is a plan view showing an example of the configuration of a wafer-level lens array having a plurality of wafer-level lenses. As shown in FIG. 1, the wafer-level lens array (1) comprises a substrate (2) and a plurality of lenses (10) arranged on the substrate (2). The plurality of lenses (10) are formed to be arranged in one or two dimensions with respect to the substrate (2). The lenses (10) formed on the wafer-level lens array (1) are then cut and divided one by one.

[0265] For this reason, wafer-level lenses have the advantage of excellent production efficiency, as hundreds or more lenses can be produced at once.

[0266] Furthermore, wafer-level lenses have the advantage of enabling the production of thin and compact lenses, which were previously limited by injection molding. The size of wafer-level lenses typically has a diameter of about 1 to 10 mm and a thickness of about 100 to 2000 μm. Taking advantage of these sizes, wafer-level lenses are well-suited for use in cameras of electronic devices such as smartphones, tablet terminals, and notebook personal computers.

[0267] The lens resin composition of the present embodiment can form a cured lens product having low curing shrinkage, high refractive index, high light transmittance, and high heat resistance, and is therefore suitable for use in wafer-level lenses where thinness and small size are desired.

[0268] [Curing material for lenses]

[0269] A cured lens product according to the present embodiment can be obtained by curing the above-described lens resin composition.

[0270] The curing shrinkage rate of the lens cured product according to the present embodiment is preferably 1.0% or more and 5.0% or less, more preferably 1.2% or more and 4.0% or less, and more preferably 1.5% or more and 3.0% or less. The curing shrinkage rate can be obtained by the above-described procedure as a procedure for measuring the curing shrinkage rate of the lens cured product (α).

[0271] The refractive index of the lens cured material according to the present embodiment is preferably 1.57 or higher, more preferably 1.58 or higher, and more preferably 1.59 or higher. The refractive index can be obtained by the above-described procedure as the procedure for measuring the refractive index of the lens cured material (α).

[0272] It is preferable that the light transmittance in the thickness direction of the cured material for a lens according to the present embodiment be 80% or more. The light transmittance can be obtained by the above-described procedure as a procedure for measuring the light transmittance of the cured material (α) for a lens.

[0273] The rate of change in light transmittance in the thickness direction of the lens cured article according to the present embodiment after heating (125°C for 168 hours) is preferably 10% or less, more preferably 5% or less, and more preferably 2% or less. The rate of change in light transmittance after heating (125°C for 168 hours) can be obtained by the above-described procedure as the measurement procedure for the rate of change in light transmittance after heating (125°C for 168 hours) of the lens cured article (α).

[0274] The cured lens material according to the present embodiment combines low curing shrinkage, high refractive index, high light transmittance, and high heat resistance, so it is suitable for use in wafer-level lenses where thinness and small size are desired.

[0275] [lens]

[0276] The lens according to the present embodiment comprises the above-described hardened material for the lens.

[0277] The lens according to the present embodiment can be manufactured, for example, by imprint molding. Imprint molding is a processing technique in which a resin composition for a lens is inserted into a lens molding die to transfer a pattern. The resin composition for a lens inserted into the lens molding die is cured by heating or light irradiation.

[0278] Light irradiation is performed using, for example, mercury lamps, xenon lamps, carbon arc lamps, metal halide lamps, sunlight, electron sources, laser light sources, LED light sources, etc., with an integrated irradiation dose of, for example, 500 to 5000 mJ / cm² 2 This can be done by investigating within the range that becomes [it].

[0279] A lens resin composition (cured lens material) that is inserted into a lens molding die and cured may be used as a lens as is, but it may also be laminated with other materials.

[0280] Examples of other materials laminated with cured materials for lenses include glass. Since glass comes in a wide variety and can be selected for its high refractive index, it is well-suited as a material for lenses requiring high optical properties. Additionally, glass has the advantage of excellent heat resistance.

[0281] In addition, resin may be used. Resin has excellent processability, making it suitable for forming lenses simply and at a low cost.

[0282] In addition, when a wafer-level molding die is used as the mold for forming lenses, a wafer-level lens array is obtained, and lenses are obtained by cutting and dividing the obtained wafer-level lens array one by one. The wafer-level lens array is as described above.

[0283] The lens according to the present embodiment combines low curing shrinkage rate, high refractive index, high light transmittance, and high heat resistance, so it is suitable for use as a wafer-level lens where thinness and small size are desired.

[0284] The diameter of the wafer level lens is typically 1 to 10 mm, preferably 1 to 5 mm. In addition, the thickness of the wafer level lens is typically 100 to 2000 μm, preferably 100 to 1000 μm.

[0285] Wafer-level lenses are suitable for use in cameras of electronic devices such as smartphones, tablet terminals, and notebook personal computers.

[0286] Although embodiments of the present invention have been described above, these are examples of the invention, and various configurations other than those described above may be adopted.

[0287] Furthermore, the present invention is not limited to the aforementioned embodiments, and modifications, improvements, etc. within the scope of achieving the purpose of the present invention are included in the present invention.

[0288] Examples

[0289] Hereinafter, embodiments of the present invention will be described in detail based on examples, but the embodiments of the present invention are not limited to these examples.

[0290] <Preparation of Resin Composition for Lenses>

[0291] A lens resin composition was obtained by heating the raw materials listed in Table 1 at 50°C and stirring and mixing them until uniform.

[0292] The raw materials listed in Table 1 are as follows.

[0293] · Photocationic polymerization initiator(X)

[0294] Triarylsulfonium-tetrakispentafluorophenyl gallate, manufactured by San Apro Corp., Product name: CPI-310FG

[0295] · Other photocationic polymerization initiators

[0296] Photocationic polymerization initiator represented by the following formula, manufactured by San Apro Corp., Product name: CPI-210S

[0297] [Chemical Formula 15]

[0298]

[0299] · Epoxy compound (Y)

[0300] Bisphenol A type epoxy resin, manufactured by DIC Co., Ltd., Product name: EXA-850CRP, Epoxy equivalent: 158–168 g / eq

[0301] · Single-acting epoxy compound (Z)

[0302] o-phenylphenol glycidyl ether, manufactured by Yokkaichi Synthetic Co., Ltd., Product name: OPP-EP

[0303] · Oxetane compound (W)

[0304] Biphenyl-type oxetane compound, Xylilene bis-oxetane, manufactured by DOA Synthetic Co., Ltd., Product name: Aaron Oxetane OXT-121

[0305] · Adhesion-imparting agent

[0306] Silane coupling agent, 3-Glycidoxypropyltrimethoxysilane, Manufactured by Shin-Etsu Chemical Co., Ltd., Product name: KBM-403

[0307] · Antioxidant

[0308] Phenolic antioxidant, pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], manufactured by ADEKA Co., Ltd., Product name: ADEKA Stav AO-60

[0309] · Light stabilizer

[0310] Hindered amine-based light stabilizer, bis(1,2,2,6,6-pentamethyl-4-piperidyl sebate, manufactured by ADEKA Co., Ltd., Product name: ADEKA Starve LA-72

[0311] <Viscosity>

[0312] The viscosity of the lens resin composition was measured using an E-type viscometer (TVE-25L, manufactured by Toki Sangyo Co., Ltd.) under conditions of a temperature of 25°C and a rotation speed of 2.5 rpm. The cone plate was appropriately selected from 1°34'×R24, 3°×R14, and 3°×R9.7 depending on the viscosity of the sample. The results are shown in Table 1.

[0313] <Production of Cured Materials for Lenses>

[0314] A glass substrate (9.0×10.0×0.7mm, Eagle-XG, manufactured by CORNING) was immersed in Novec (registered trademark) 1720 (fluorinated silane-based release agent, manufactured by 3M, Inc.), heated at 100°C for 25 minutes under a nitrogen atmosphere, and rinsed with Novec (registered trademark) 7100 (fluorinated solvent, manufactured by 3M, Inc.) to obtain a glass substrate with a completed release treatment.

[0315] A lens resin composition was dropped onto a release-treated glass substrate, and a silicone spacer with a thickness of 250 μm was inserted into the release-treated glass substrate and secured with a clip. In this case, an electrodeless lamp (H bulb) was used, with an irradiation intensity of 150 mW / cm² at a wavelength of 365 nm and an integrated irradiation dose of 3000 mJ / cm². 2 The lens resin composition was cured by UV exposure to such an extent.

[0316] Next, the cured lens resin composition was released from a glass substrate, and a cured lens product was obtained by heating at 120°C for 30 minutes under a nitrogen atmosphere.

[0317] <Curing Shrinkage Rate>

[0318] First, the specific gravity d1 of the lens resin composition was determined according to JIS Z 8804:2012 (Method for measuring density and specific gravity of liquids). (Meanwhile, if the lens resin composition contains volatile components, the specific gravity of the non-volatile components is determined excluding them; however, the resin composition of this embodiment does not contain volatile components.)

[0319] Next, the specific gravity d2 of the lens cured material was determined according to JIS Z 8807:2012 (Method for measuring density and specific gravity of solids). Using the calculated specific gravity value, the curing shrinkage rate was calculated by the following formula. The results are shown in Table 1.

[0320] Curing shrinkage rate (%) = (1 - d1 / d2) × 100

[0321] <Measurement of Refractive Index>

[0322] The refractive index of the lens cured material was measured using an Abbe refractometer (DR-M2, manufactured by Atago Co., Ltd.). RE-3520 (589 nm, D line, manufactured by Atago Co., Ltd.) was used as the interference filter and RE-1196 (monobromonaphthalene, manufactured by Atago Co., Ltd.) was used as the intermediate solution, and the measurement was performed with the sample temperature set to 25°C. The results are shown in Table 1.

[0323] <Light Transmittance>

[0324] The light transmittance in the thickness direction of the lens cured material was measured under the following conditions to obtain the light transmittance T1. Meanwhile, the measurement was performed by attaching the lens cured material to an integrating sphere, and the light-receiving surface was set to an arbitrary surface.

[0325] (Measurement conditions)

[0326] Measuring device: UH4150 (Ultraviolet-Visible-Near-Infrared Spectrophotometer manufactured by Hitachi High-Tech Science)

[0327] Measurement method: Transmission method

[0328] Measurement wavelength: 400nm

[0329] Reference: Waiting

[0330] Detector: Integrating sphere / photomultiplier tube (200 nm–850 nm)

[0331] Integrating sphere: PbS(850nm∼2600nm)

[0332] <Rate of change in light transmittance after heating (125℃ for 168 hours)>

[0333] First, the cured material for the lens was heated for 168 hours in an oven set to 125°C under an air atmosphere. Afterward, the light transmittance T2 after heating was obtained by measuring the light transmittance in the thickness direction under the above conditions, and was calculated using the following formula. The results are shown in Table 1.

[0334] Rate of change in light transmittance after heating (125℃ for 168 hours) (%)

[0335] =(T1-T2) / T1×100

[0336] <Evaluation of Glass Adhesion>

[0337] A glass substrate (7.0×7.0×0.21mm, D263T ECO, manufactured by SCHOTT) was immersed in Novec (registered trademark) 1720 (fluorinated silane-based release agent, manufactured by 3M, Inc.), heated at 100°C for 25 minutes under a nitrogen atmosphere, and rinsed with Novec (registered trademark) 7100 (fluorinated solvent, manufactured by 3M, Inc.) to obtain a glass substrate with a completed release treatment.

[0338] A lens resin composition was dropped onto a glass substrate that had undergone release treatment, and a silicone spacer with a thickness of 250 μm was inserted into a glass substrate that had not undergone release treatment (7.0 × 7.0 × 0.21 mm, D263T ECO, manufactured by SCHOTT) and secured with a clip. At this time, the amount of lens resin composition dropped was adjusted so that the diameter of the wet and spread resin composition was about 5 mm.

[0339] Regarding this, using an electrodeless lamp (H bulb), the irradiation intensity at a wavelength of 365 nm is 150 mW / cm² and the integrated irradiation dose is 3000 mJ / cm² 2 The lens resin composition was cured by UV exposure. Subsequently, a release-treated glass substrate was released from the cured lens resin composition, and by heating at 120°C for 30 minutes under a nitrogen atmosphere, a laminate of the cured lens material and the glass substrate (resin diameter 5 mm) was obtained.

[0340] In addition, a laminate of a lens-cured material and a glass substrate (resin diameter 40 mm) was obtained by the same operation as above, except that the amount of the resin composition for the lens was adjusted so that the diameter of the resin composition was 40 mm.

[0341] At this time, the laminate was evaluated by designating A as no delamination was confirmed at the interface between the lens cured material and the glass substrate, B as no delamination occurred but the glass substrate was significantly deformed, and C as the resin easily delaminated from the substrate. The results are shown in Table 1.

[0342]

[0343] The rate of change in light transmittance after heating in the example was reduced compared to the comparative example. This indicates that discoloration caused by heating was suppressed. Furthermore, the curing shrinkage rate, refractive index, and light transmittance of the example were at a high level comparable to that of the comparative example. From these points, it can be seen that the lens resin composition of the present embodiment possesses low curing shrinkage rate, high refractive index, high light transmittance, and high heat resistance.

[0344] Meanwhile, when comparing the examples, it can be seen that glass adhesion is improved when one or more selected from the group consisting of a single-acting epoxy compound (Z), an oxetane compound, and an adhesion promoter are included.

[0345] This application claims priority based on Japanese application No. 2022-000161 filed on January 4, 2022, and incorporates all of the disclosures thereof herein. Explanation of the symbols

[0346] 1 Wafer Lens Array 2 substrates 10 lenses

Claims

Claim 1 A lens resin composition comprising a photocationic polymerization initiator (X) comprising a salt formed from an anion represented by general formula (1) and a cation, and an epoxy compound (Y) comprising two or more epoxy groups within a molecule, wherein the epoxy compound (Y) is represented by general formula (2), and the lens resin composition is applied to a glass plate to a thickness of 250 μm, with a wavelength of 365 nm, an irradiation intensity of 150 mW / cm, and an integrated irradiation dose of 3000 mJ / cm. 2 A lens resin composition in which a cured product obtained by UV exposure under the conditions of [condition] and heating under a nitrogen atmosphere at 120°C for 30 minutes satisfies the requirements of (B) below (provided, an energy-ray curable composition comprising an acid-generating agent containing an onium gallate salt represented by the following general formula (I) and an onium phosphate salt represented by the following general formula (II) and a cationic polymerizable compound is excluded). (B) The refractive index of the cured product is 1.57 or higher. [Chemical Formula 1] (In general formula (1), R 1 ~R 4 Each represents an alkyl group having 1 to 18 carbon atoms or an aryl group having 6 to 14 carbon atoms independently.)[Chemical Formula 2] (In general formula (2), R 5 , R 6 , R 8 and R 9 Each independently represents a hydrogen atom, a C1- to C4 alkyl group, or a trifluoromethyl group, and R 7 ☐ each independently represents a hydrogen atom or a glycidyl group, and n is the average number of repetitions and represents a real number in the range of 0 to 30.)[(R 5 ) n+1 -E] + [(R 1 )(R 2 )(R 3 )(R 4 )Ga] - (I)[Equation(I), R 1 ~R 4 is independently an alkyl group having 1 to 18 carbon atoms or Ar, provided that at least one is Ar, and Ar is an aryl group having 6 to 14 carbon atoms (excluding the number of carbon atoms of the following substituents), wherein part of the hydrogen atoms in the aryl group are an alkyl group having 1 to 18 carbon atoms, an alkyl group having 1 to 8 carbon atoms substituted with a halogen atom, an alkenyl group having 2 to 18 carbon atoms, an alkynyl group having 2 to 18 carbon atoms, an aryl group having 6 to 14 carbon atoms, a nitro group, a hydroxyl group, a cyano group, -OR 6 an alkoxy or aryloxy group represented by, R 7 Acyl group represented by CO-, R 8 Acyloxy group represented as COO-, -SR 9 An alkylthio group or arylthio group represented by , -NR 10 R 11 It may be substituted with an amino group represented by , or a halogen atom, and R 6 ~R 9 is an alkyl group having 1 to 8 carbon atoms or an aryl group having 6 to 14 carbon atoms, R 10 and R 11 is a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or an aryl group having 6 to 14 carbon atoms; E represents an element with valence n from groups 15 to 17 (IUPAC notation), n is an integer from 1 to 3, and R 5 is an organic group bonded to E, and R 5 The number of is n+1, and (n+1) R 5 Each may be identical or different from each other, and two or more R 5 They may form a ring structure containing element E either directly or through -O-, -S-, -SO-, -SO2-, -NH-, -CO-, -COO-, -CONH-, alkylene groups, or phenylene groups.][(R 5 ) n+1 -E] + [(Rf) b PF 6-b ] - (II)[In Formula (II), Rf represents an alkyl group in which 80% or more of the hydrogen atoms are substituted with fluorine atoms. b represents the number thereof and is an integer from 1 to 5. The b Rfs may each be identical or different. R 5 The definitions of , E, and n are the same as the definitions in general formula (1). Claim 2 delete Claim 3 A resin composition for lenses according to claim 1, wherein the epoxy equivalent of the epoxy compound (Y) is 100 g / eq or more and 200 g / eq or less. Claim 4 A lens resin composition according to claim 1 or 3, wherein the content of the epoxy compound (Y) is 40 mass% or more of the non-volatile component of the lens resin composition. Claim 5 A resin composition for a lens according to claim 1 or 3, wherein the photocationic polymerization initiator (X) comprises an anion represented by either formula (3) or (4) as an anion. [Chemical Formula 3] [Chemical Formula 4] Claim 6 A resin composition for a lens according to claim 1 or 3, wherein the photocationic polymerization initiator (X) comprises a sulfonium ion as a cation. Claim 7 A resin composition for a lens according to claim 1 or 3, further comprising a monofunctional epoxy compound (Z) represented by general formula (5). [Chemical Formula 5] (In general formula (5), A is selected from single bonds, oxygen atoms, and sulfur atoms, and R 10 is an alkylene having 1 to 8 carbon atoms, and any methylene group may be substituted with an oxygen atom. Claim 8 A lens resin composition according to claim 7, wherein the single-acting epoxy compound (Z) is o-phenylphenol glycidyl ether. Claim 9 A resin composition for a lens, wherein, in claim 1 or 3, it further comprises an oxetane compound (W). Claim 10 A resin composition for lenses according to claim 9, wherein the oxetane compound (W) is a biphenyl-type oxetane compound. Claim 11 A lens resin composition according to claim 1 or 3, wherein the viscosity of the lens resin composition when measured with an E-type viscometer under conditions of a temperature of 25°C and a rotation speed of 2.5 rpm is 100 mPa·s or more and 5000 mPa·s or less. Claim 12 In claim 1 or 3, the resin composition for the lens is applied onto a glass plate to a thickness of 250 μm, and the wavelength is 365 nm, the irradiation intensity is 150 mW / cm², and the integrated irradiation dose is 3000 mJ / cm². 2 A resin composition for lenses, wherein a cured product obtained by UV exposure under conditions and heating under a nitrogen atmosphere at 120°C for 30 minutes satisfies the requirements of (A), (C), and (D) below. (A) The curing shrinkage rate of the cured product is 1.0% or more and 5.0% or less. (C) The light transmittance in the thickness direction of the cured product is 80% or more. (D) The rate of change in light transmittance in the thickness direction of the cured product after heating (125°C for 168 hours) is 10% or less. Claim 13 A lens resin composition used in a wafer-level lens, according to claim 1 or 3. Claim 14 A cured lens product obtained by curing a resin composition for lenses described in claim 1 or 3. Claim 15 A lens having a cured material for a lens as described in claim 14.

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