JP5878830B2 - Adhesive composition for optical parts - Google Patents

Description

  The present invention relates to an adhesive composition for optical parts used for bonding optical elements such as lenses, prisms and optical waveguides.

  Conventionally, in assembling optical devices such as cameras and microscopes, transparent resins such as balsams and epoxy resins have been used as adhesives to join lenses and prisms. In recent years, with the development of the optoelectronics industry, applications for joining optical elements with advanced optical functions such as optical fibers and microlenses are increasing, and bisphenol A type epoxy (meth) acrylate and urethane (meth). Adhesives containing radically polymerizable monomers such as acrylates are also widely used.

  In particular, when optical circuits such as optical modulators and optical switches are manufactured by joining optical waveguide elements and microlenses, optical fibers, etc., and for optical components that require advanced optical properties such as joining thin lenses. In joining, an adhesive having a high refractive index is required. As such an adhesive, for example, Patent Documents 1 to 3 disclose an adhesive composition using a sulfur-containing (meth) acrylate and a photocurable resin composition. Further, for example, Patent Document 4 discloses an active energy ray-curable composition using urethane (meth) acrylate having a diphenylsulfone structure, which is useful as an adhesive.

JP-A-11-5952 Japanese Patent Laid-Open No. 2002-97224 JP 2006-526037 A JP 2011-157543 A JP 2011-178985 A

  However, in the case of sulfur-containing (meth) acrylate and urethane (meth) acrylate having a diphenylsulfone structure, which are the main components described in the above-mentioned patent documents, 4,4′-dimercaptodiphenyl sulfide dimethacrylate is a bisphenol A type. Although it has a higher refractive index than a compound having an aromatic ring, such as epoxy (meth) acrylate, it cannot meet the requirements for a high refractive index associated with the thinning of optical lenses, etc. In general, in order to absorb light having a wavelength of 450 nm or less, there is a problem in that it is colored yellow and transparency tends to be lowered.

  As a compound having a high refractive index and high transparency with respect to the above problems, Patent Document 5 discloses a compound and a polymer having a dinaphthothiophene skeleton. In Examples of Patent Document 5, a photocured film prepared by diluting a photopolymerizable composition using dinaphthothiophene having an ethylenically unsaturated double bond with a solvent such as ethyl acetate is disclosed. (Paragraph number [0143]). However, when used for bonding optical parts, it may cause a decrease in strength or outgassing due to the influence of residual solvent, and it may not be possible to obtain good reliability, or it may be crystalline when stored for a long time. The components are liable to be precipitated in the composition, resulting in a disadvantage that the refractive index varies or cannot be applied. In addition, since a dimensional accuracy cannot be ensured even in a micro-molding process such as photo-molding and nano-imprint, it is often difficult to use a solvent, and it is difficult to use a composition diluted with a solvent.

  This invention is made | formed in view of such a situation, and provides the adhesive composition for optical components which has a high refractive index, high transparency, and does not require the use of a solvent.

According to the present invention,
(1) As a component (A), a dinaphthothiophene compound having one or more polymerizable functional groups having an ethylenically unsaturated double bond represented by the following general formula (1):
(In the general formula (1), each X is independently a single bond, a divalent organic group or a divalent atom, each R ¹ is independently a hydrogen atom or a methyl group, and c + d is C is an integer of 0 to 4 and d is an integer of 0 to 4 on condition that it is an integer of 1 to 4. When X is a divalent organic group, X is an oxygen atom, An alkylene group, an aralkylene group, an alkenylene group, an ester bond, an amide bond, an imide bond, or an alkylene group containing these bonds in the main chain, an arylene group, an aralkylene group, a divalent group that may contain a hetero atom consisting of a sulfur atom or a nitrogen atom A substituted aromatic group, a divalent substituted heteroaromatic group, a divalent substituted silyl group, and when X is a divalent atom, X may be an oxygen atom, a sulfur atom, or another atom. And a tin atom that may have a bond with other atoms A phosphorus atom that may have a bond, wherein X may be bonded to any of the substitutable carbon atoms in the naphthalene ring to which they are bonded, wherein (R) a or (R) b is means a or b identical or different substituents, which may be attached to any of the substitutable carbon atoms in the naphthalene ring to which they are attached, and each R is independently an organic A group, a hydroxyl group, an amino group, a nitro group, a thiol group, a sulfo group, a halogen atom, or an optionally substituted silyl group, a is an integer of 0 to 5, and b is an integer of 0 to 5. (It is an integer.)
(B) As a component, a monofunctional (meth) acrylate containing one or more aromatic rings,
(C) As a component, radical photopolymerization initiator,
The content ratio of the component (A) is in the range of 15 to 50 parts by mass, and the content ratio of the component (B) is in the range of 50 to 85 parts by mass. An agent composition is provided.

The inventors of the present invention have been diligently studying to obtain a composition suitable for an adhesive for optical components, and the dinaphthothiophene compound as shown in the general formula (1) is used without using a solvent. When mixed with a polyfunctional epoxy acrylate and a photo radical polymerization initiator as described in [0143] of Patent Document 5, a precipitate that does not dissolve easily after standing for a while is difficult to use as an adhesive. (Comparative Example 2). Accordingly, further investigations have been made to solve such problems. When a monofunctional (meth) acrylate containing one or more aromatic rings is used in place of the polyfunctional epoxy acrylate, this is the case. It was found that no precipitates or separations were generated, or even if generated, they could be easily dissolved. Further, when a compound having an aromatic ring but not (meth) acrylate is used instead of a monofunctional (meth) acrylate containing an aromatic ring (Comparative Example 3), sufficient curing occurs even when light irradiation is performed. Thus, it was found difficult to use as an adhesive for optical components. Furthermore, when a monofunctional (meth) acrylate having no aromatic ring was used (Comparative Example 4), a precipitate that was not easily dissolved was generated. Further, when a dinaphthothiophene compound having no functional group is used instead of the dinaphthothiophene compound having a polymerizable functional group (Comparative Example 5), a precipitate that does not easily dissolve is generated. I have. Furthermore, when a dinaphthothiophene compound was not used (Comparative Example 1), the refractive index was low.
From the above, high refractive index and high transparency are achieved by the synergistic effect of the combination of a dinaphthothiophene compound having a polymerizable functional group, a monofunctional (meth) acrylate containing an aromatic ring, and a photo radical polymerization initiator. It has been found that an adhesive composition for optical parts is obtained which has a solvent and does not require the use of a solvent.

Preferably, the component (B) is a monofunctional (meth) acrylate containing one aromatic ring.
Preferably, the component (B) includes one or more selected from benzyl (meth) acrylate and phenoxyethyl (meth) acrylate.
Preferably, the polymerizable functional group is a (meth) acryloyl group or an allyl ether group.
Preferably, in the general formula (1), a = b = c = 0 and d = 1.
Preferably, the component (A) is selected from 6-methacryloylmethyl dinaphthothiophene, 6-methacryloylethyl dinaphthothiophene, 2,12-diallyl ether dinaphthothiophene, and 3,11-diallyl ether dinaphthothiophene. Including one or more.
Preferably, the content ratio of the component (C) is 0.2 to 10 parts by mass with respect to the total amount of the composition.

  The adhesive composition of the present invention is an adhesive composition for optical components containing a dinaphthothiophene compound having a polymerizable functional group, a monofunctional (meth) acrylate having an aromatic ring, and a radical polymerization initiator in a specific ratio. Therefore, it has the characteristics of having a high refractive index and high transparency required for adhesion of optical components. In addition, since the adhesive composition of the present invention does not require the use of a solvent, it can avoid the problem of strength reduction and outgas generation due to the influence of the residual solvent, and has high dimensional accuracy even in a fine molding process. Can be secured.

<Explanation of terms>
In the present specification, the adhesive composition means an adhesive for bonding parts to each other, particularly an adhesive suitably used for bonding optical parts.

  The components of the adhesive composition according to this embodiment will be described.

<(A) component: dinaphthothiophene compound>
The energy beam curable resin composition according to the present embodiment has, as component (A), dinaphtho having at least one polymerizable functional group having an ethylenically unsaturated double bond represented by the following general formula (1). It has a thiophene compound.
(In the general formula (1), each X is independently a single bond, a divalent organic group or a divalent atom, each R ¹ is independently a hydrogen atom or a methyl group, and c + d is C is an integer of 0 to 4 and d is an integer of 0 to 4 on condition that it is an integer of 1 to 4. When X is a divalent organic group, X is an oxygen atom, An alkylene group, an aralkylene group, an alkenylene group, an ester bond, an amide bond, an imide bond, or an alkylene group containing these bonds in the main chain, an arylene group, an aralkylene group, a divalent group that may contain a hetero atom consisting of a sulfur atom or a nitrogen atom A substituted aromatic group, a divalent substituted heteroaromatic group, a divalent substituted silyl group, and when X is a divalent atom, X may be an oxygen atom, a sulfur atom, or another atom. And a tin atom that may have a bond with other atoms A phosphorus atom that may have a bond, wherein X may be bonded to any of the substitutable carbon atoms in the naphthalene ring to which they are bonded, wherein (R) a or (R) b is means a or b identical or different substituents, which may be attached to any of the substitutable carbon atoms in the naphthalene ring to which they are attached, and each R is independently an organic A group, a hydroxyl group, an amino group, a nitro group, a thiol group, a sulfo group, a halogen atom, or an optionally substituted silyl group, a is an integer of 0 to 5, and b is an integer of 0 to 5. (It is an integer.)

  Examples of the polymerizable functional group include a vinyl group, a styryl group, a vinyl ether group, an allyl group, an allyl ether group, a (meth) acryloyl group, an acrylonitrile group, and the (meth) acryloyl group or allyl group in terms of transparency. Ether groups are preferred, and (meth) acryloyl groups are particularly preferred.

  Specific examples of the dinaphthothiophene compound include 6-vinyldinaphthothiophene, 6- (meth) acryloyloxymethyldinaphthothiophene, 6- (meth) acryloyloxyethyl dinaphthothiophene, 6-vinyl ether dinaphthothiophene, 6-allyldinaphthothiophene, 6-allyloxydinaphthothiophene, 2,12-divinyldinaphthothiophene, 3,11-divinyldinaphthothiophene, 5,9-divinyldinaphthothiophene, 2,12-di (meth) Acryloyloxymethyldinaphthothiophene, 3,11-di (meth) acryloyloxymethyldinaphthothiophene, 2,12-diallyloxymethyldinaphthothiophene, 3,11-diallyloxydinaphthothiophene, 2,12-divinyloxymethyl Ginaft Ofene, 3,11-divinyloxydinaphthothiophene, etc. are mentioned, but in terms of transparency, 6-methacryloyloxymethyldinaphthothiophene, 6-methacryloyloxyethyldinaphthothiophene, 2,12-diallyloxydinaphthothiophene And 3,11-diallyloxydinaphthothiophene are preferred, and 6- (meth) acryloyloxymethyldinaphthothiophene is particularly preferred.

  The content ratio of the component (A) is preferably 15 to 50 parts by mass with respect to the total amount of the adhesive composition, and particularly 20 to 20 in terms of refractive index, transparency, and compatibility with the component (B). More preferred is 40 parts by weight.

  The dinaphthothiophene-based compound can be produced by the production method exemplified in JP 2011-178985 A (above Patent Literature 5), but not limited to this method, any one produced by any production method can be used. it can.

<(B) component: monofunctional (meth) acrylate>
The adhesive resin composition of the present invention contains a monofunctional (meth) acrylate having one or more aromatic rings as the component (B). The number of aromatic rings is, for example, 1, 2, 3, and preferably one.

  Specific examples of the monofunctional (meth) acrylate include benzyl (meth) acrylate, phenoxyethyl (meth) acrylate, phenoxydiethylene glycol (meth) acrylate, phenoxytetraethylene glycol (meth) acrylate, and phenoxyhexaethylene glycol (meth) acrylate. , Nonylphenyl (meth) acrylate, ethylene oxide modified nonylphenyl (meth) acrylate, phthalic acid modified (meth) acrylate, naphthyl (meth) acrylate, bisphenylfluorene (meth) acrylate, 2- (o-phenylphenoxy) ethyl acrylate Etc., but benzyl (meth) acrylate or phenoxyethyl (meth) acrylate may be used from the viewpoint of compatibility with component (A), refractive index, and transparency. Preferred.

  The content ratio of the component (B) is preferably 50 to 85 parts by mass with respect to the total amount of the adhesive composition, and particularly in terms of refractive index, transparency, and compatibility with the component (A), 60 to 80 parts by mass is more preferable.

  The adhesive composition of the present invention may contain a monofunctional (meth) acrylate compound having no aromatic ring or a polyfunctional (meth) acrylate as long as the effects of the invention are not impaired.

<(C) component: radical photopolymerization initiator>
The adhesive resin composition of the present embodiment contains (C) a radical photopolymerization initiator. The radical photopolymerization initiator is not particularly limited as long as it is a compound that generates radicals when irradiated with energy rays.

  Examples of the photo radical polymerization initiator include benzyl derivatives such as benzyl, benzoin, benzoin benzoic acid, benzoin ethyl ether, benzoin isopropyl ether and benzoin isobutyl ether, benzophenone derivatives such as benzophenone and 4-phenylbenzophenone, and 2,2-diethoxy. Alkylacetophenone derivatives such as acetophenone and benzyldimethyl ketal, 1-hydroxycyclohexyl phenyl ketone, 1- (4-isopropylphenyl) 2-hydroxy-2-methylpropan-1-one, 1- (4- (2-hydroxyethoxy) -Phenyl) -2-hydroxy-2-methyl-1-propan-1-one, α-hydroxyacetophenone derivatives such as 2-hydroxy-2-methyl-1-phenylpropan-1-one, Sudiethylaminobenzophenone, 2-methyl-1- (4- (methylthio) phenyl) -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -1- Α-Aminoalkylacetophenone derivatives such as butanone-1, isobutyryl-methylphosphinic acid methyl ester, isobutyryl-phenylphosphinic acid methyl ester, pivaloyl-phenylphosphinic acid methyl ester, 2-ethylhexanoyl-phenylphosphinic acid methyl ester Ester, pivaloyl-phenylphosphinic acid isopropyl ester, p-toluyl-phenylphosphinic acid methyl ester, o-toluyl-phenylphosphinic acid methyl ester, 2,4-dimethylbenzoyl-phenylphosphinic acid Tilester, p-3 tertiary butylbenzoyl-phenylphosphinic acid isopropyl ester, bivaloyl- (4-methylphenyl) -phosphinic acid methyl ester, pivaloyl-phenylphosphinic acid vinyl ester, acryloyl-phenylphosphinic acid methyl ester, isobutyryl- Diphenylphosphine oxide, pivaloyl-diphenylphosphine oxide, 1-methyl-1-cyclohexanoyl-diphenylphosphine oxide, 2-ethylhexanoyl-diphenylphosphine oxide, p-toluyl-diphenylphosphine oxide, o-toluyl -Diphenylphosphine oxide, p-tert-butylbenzoyl-diphenylphosphine oxide, (meth) acryloyldiphenylphosphine Finoxide, benzoyl-diphenylphosphine oxide, 2,2-dimethyl-heptanoyl-diphenylphosphine oxide, terephthaloyl-bis-diphenylphosphine oxide, adipoyl-bis-diphenylphosphine oxide, 2,6-dimethylbenzoyl-diphenylphosphine Fin oxide, 2,6-dimethoxybenzoyl-phenylphosphinic acid methyl ester, 2,6-dimethylbenzoyl-diphenylphosphine oxide, 2,6-dimethoxybenzoyl-diphosphine oxide, 2,4,6-trimethylbenzoyl- Phenylphosphinic acid methyl ester, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, 2,3,6-trimethylbenzoyl-diphe Ruphosphine oxide, 2,4,6-trimethylbenzoyl-triphosphinic acid methyl ester, 2,4,6-trimethoxybenzoyl-diphenylphosphine oxide, 2,6-dichlorobenzoyl-phenylphosphinic acid ester, 2, 6-dichlorobenzoyl-diphenylphosphine oxide, 2,3,4,6-tetramethylbenzoyl-diphenylphosphine oxide, 2,6-dibromobenzoyl-diphenylphosphine oxide, 2,6-dimethylbenzoyldiphenylphosphine Oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoyl-phenylphosphinic acid methyl ester, 2,6-dichlorobenzoyl- or 2,6- Acyl such as methoxybenzoyl-diphenylphosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethyl-pentylphosphine oxide Phosphine oxide derivative, 1,2-octanedione, 1-[-4- (phenylthio)-, 2- (O-benzoyloxime)], ethanone 1- [9-ethyl-6- (2-methylbenzoyl)- And oxime ester compounds such as 9H-carbazol-3-yl] -1- (O-acetyloxime). In these, 1 or more types which consist of an alkyl acetophenone derivative, (alpha) -hydroxy acetophenone, and phosphine oxides are preferable at the point which is excellent in reactivity and transparency. These can be used alone or in combination of two or more.

  (C) It is preferable to make the content rate of a component contain in the ratio of 0.1-10 mass parts with respect to the total amount of an adhesive composition, and 0.5-5 mass parts is especially more preferable. If it exists in the range of 0.1-10 mass parts, sclerosis | hardenability will not worsen and transparency will not fall.

<Other additives>
As long as the purpose of the present embodiment is not impaired, an antioxidant, a silane coupling agent, various elastomers such as an acrylic rubber and a urethane rubber, a photosensitizer, a light stabilizer, a solvent, an extender, a filler, a reinforcing material, Additives such as plasticizers, thickeners, dyes, pigments, flame retardants and surfactants may be contained.

  The adhesive composition having the above configuration can be made into a cured body by irradiation with energy rays.

  In addition, since the adhesive composition having the above-described configuration can adhere parts to each other by irradiation with energy rays, it has excellent optical properties such as high transparency and high refractive index. A joined body of an optical component such as a film can be provided.

  Furthermore, the adhesive composition having the above structure is excellent in optical properties such as high transparency and a high refractive index, so that a liquid crystal panel, an organic electroluminescence panel, a touch panel, a projector, a smartphone, a mobile phone and the like that require bonding of advanced optical components are required. Telephones, digital cameras, digital movie display devices, light pickup devices such as optical pickups, LEDs, printers, copiers, and light irradiators, energy members such as solar cells and lithium ion batteries, and various sensor components such as CCDs and CMOSs Semiconductor devices such as flash memory, DRAM, and semiconductor laser can be provided.

  About the manufacturing method of the adhesive composition which concerns on this embodiment, if said material can fully be mixed, there will be no restriction | limiting in particular. The mixing method of the material is not particularly limited, and examples thereof include a stirring method using a stirring force accompanying rotation of a propeller, a method using a normal disperser such as a planetary stirrer by rotation and revolution, and the like. These mixing methods are preferable because stable mixing can be performed at low cost.

  After performing the above mixing, the adhesive composition can be cured by irradiation with energy rays using the following light source.

  In the present embodiment, the light source used for curing and adhering the adhesive composition is not particularly limited. However, a halogen lamp, a metal halide lamp, a high power metal halide lamp (containing indium, etc.), a low pressure mercury lamp, and a high pressure mercury lamp. , Ultra high pressure mercury lamp, xenon lamp, xenon excimer lamp, xenon flash lamp, light emitting diode (hereinafter referred to as LED), and the like. These light sources are preferable in that they can efficiently irradiate energy rays corresponding to the reaction wavelengths of the respective radical photopolymerization initiators.

  Each of the light sources has a different emission wavelength and energy distribution. Therefore, the light source is appropriately selected depending on the reaction wavelength of the photopolymerization initiator. Natural light (sunlight) can also be a reaction initiation light source.

  The light source may perform direct irradiation, condensing irradiation using a reflecting mirror, or condensing irradiation using a fiber or the like. A low wavelength cut filter, a heat ray cut filter, a cold mirror, or the like can also be used.

  Since the adhesive composition having the above configuration has both a high refractive index and high transparency, an adhesive suitable for bonding optical components can be provided.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

  In the examples, the following compounds were used.

(A) Dinaphthothiophene compound The dinaphthothiophene compound used what was manufactured with the synthesis method ([Example] [0106]-[0121]) as described in Unexamined-Japanese-Patent No. 2011-178985 (the said patent document 5). .
(A-1) 6-methacryloyloxymethyldinaphthothiophene (abbreviation: DNTMA)
(A-2) 6-vinyldinaphthothiophene (abbreviation: VDNT)
(A-3) 6-methacryloyloxyethyl dinaphthothiophene (abbreviation: EDNTMA)
(A-4) 2,12-diallyloxydinaphthothiophene (abbreviation: DAODNT)
(A-5) 3,11-diallyloxydinaphthothiophene (abbreviation: i-DAODNT)
(A-6) Dinaphthothiophene (abbreviation: DNT)

(B) Monofunctional (meth) acrylate (B-1) benzyl methacrylate having an aromatic ring (“Light Ester BZ” manufactured by Kyoeisha Chemical Co., Ltd.)
(B-2) Benzyl acrylate (“Biscoat # 160” manufactured by Osaka Organic Chemical Industry Co., Ltd.)
(B-3) Phenoxyethyl methacrylate (Kyoeisha Chemical Co., Ltd. “Light Ester PO”)
(B-4) Phenoxyethyl acrylate (Kyoeisha Chemical Co., Ltd. “Light acrylate PO-A”)
(B-5) 2- (o-phenylphenoxy) ethyl acrylate (“NK Ester A-LEN-10” manufactured by Shin-Nakamura Chemical Co., Ltd.)

(C) Photoradical polymerization initiator (C-1) Benzyldimethyl ketal ("Irgacure 651" manufactured by BASF)
(C-2) 1-hydroxy-cyclohexyl phenyl ketone ("Irgacure 184" manufactured by BASF)
(C-3) Bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide (“Irgacure 819” manufactured by BASF)

For comparison, the following was used.
(D-1) Bisphenol A type epoxy acrylate (“Epoxy ester 3002M” manufactured by Kyoeisha Chemical Co., Ltd.)
(D-2) Styrene (“Styrene” manufactured by Wako Pure Chemical Industries, Ltd.)
(D-3) Methyl methacrylate ("MMA" manufactured by Mitsubishi Gas Chemical Company)

(Examples 1-14, Comparative Examples 1-5)
The raw materials of the types shown in Tables 1 and 2 were mixed at the composition ratios (units are parts by mass) shown in Tables 1 and 2 to prepare an adhesive composition, and the evaluation described below was performed. No solvent was used. Various evaluation results are shown in Tables 1 and 2. Unless otherwise specified, the test was carried out in an environment of 23 ° C. and 50% humidity.

(Liquid stability evaluation)
Prepare a sealed sample by putting 10 ml of the adhesive composition in a 30 ml vial, leave the sample in an atmosphere at a temperature of 23 ° C. for 24 hours, visually check the state of the liquid after 24 hours, and It was evaluated with.
◯: No change from before standing Δ: Precipitates and isolates were seen but redissolved by heating at 50 ° C. x: Precipitates and isolates were seen and did not dissolve even after heating at 50 ° C.

(Evaluation of refractive index)
(1) Liquid Refractive Index The liquid refractive index was evaluated by measuring the refractive index at a temperature of 25 ° C. and a wavelength of 589 nm using a multiwavelength Abbe refractometer (“DR-M2” manufactured by Atago Co., Ltd.).
(2) Refractive index of cured product The adhesive composition was poured into a silicone rubber mold having a volume of 15 mm × 15 mm × 1.0 mm, and 365 nm with an ultra-high pressure mercury lamp mounting device (“UL-750” manufactured by HOYA). A cured product test piece cured under the conditions of an irradiation intensity of 30 mW / cm ² and an integrated light quantity of 30,000 mJ / cm ² was prepared, and the refractive index was evaluated. The refractive index was evaluated by measuring the refractive index at a wavelength of 633 nm using a spectroscopic prism coupler refractive index measuring device ("MODEL 2010 PRISM COUPLER" manufactured by Metricon).

(Spectral transmittance measurement)
After applying the adhesive composition on heat-resistant glass (trade name “heat-resistant Pyrex (registered trademark) glass”, 25 mm × 25 mm × 2.0 mm) with a film thickness of 30 μm, an ultra-high pressure mercury lamp mounting device (“UL” manufactured by HOYA -750 "), a test piece cured under conditions of irradiation intensity of a wavelength of 365 nm of 50 mW / cm ² and integrated light quantity of 30,000 mJ / cm ² was prepared, and an ultraviolet-visible spectrophotometer (manufactured by Shimadzu Corporation) UV-2550 "), the transmittance was measured at 450 nm using a heat resistant glass as a reference.

<Discussion>
In each of Examples 1 to 10, excellent results were obtained in terms of liquid stability, refractive index, and spectral transmittance. However, in Example 1, since the blending ratio of the dinaphthothiophene compound was small, the refractive index was slightly low. In Example 6, since the compounding ratio of the dinaphthothiophene compound was large, the liquid stability was slightly deteriorated. In Example 10 using a dinaphthothiophene compound having a vinyl group, Examples 1 to 9 and Examples 11 to 14 using a dinaphthothiophene compound having a (meth) acryloyl group or an allyl ether group were used. In comparison, liquid stability and spectral transmittance were not preferred. This result shows the advantage of using a dinaphthothiophene compound having a (meth) acryloyl group or an allyl ether group. Furthermore, when Example 3 and Examples 11-13 were compared, when DNTMA was used like Example 3, it turned out that a refractive index and spectral transmittance become especially high. Furthermore, as in Example 14, when an acrylate having two aromatic rings was used as the component (B), the liquid stability and the spectral transmittance deteriorated.

  In Comparative Example 1, since the dinaphthothiophene compound was not used, the refractive index was not sufficient. In Comparative Example 2, since polyfunctional acrylate (bisphenol A type epoxy acrylate) was used, the liquid stability was very poor, and a test piece for evaluation of refractive index and spectral transmittance could not be prepared. In Comparative Example 3, since a compound (styrene) having an aromatic ring but not (meth) acrylate was used instead of the component (B), curing did not occur sufficiently even when light irradiation was performed. In Comparative Example 4, since monofunctional (meth) acrylate (methyl methacrylate) having no aromatic ring was used instead of component (B), the liquid stability was poor and precipitates that did not dissolve easily were generated. It was. In Comparative Example 5, since a dinaphthothiophene compound (dinaphthothiophene) having no functional group was used, the liquid stability was poor and precipitates that were not easily dissolved were generated.

Since the adhesive composition of the present invention has a high refractive index and high transparency, a liquid crystal panel, an organic electroluminescence panel, a touch panel, a projector, a smartphone, a mobile phone, a digital camera, a digital movie, an optical pickup, an LED, and a solar cell Adhesion of optical parts such as lenses, prisms, glass members, and films used in lithium ion batteries, and assembly of various parts, as well as various sensors such as CCD and CMOS, flash memory, DRAM, semiconductor elements such as semiconductor lasers It can be suitably used for bonding glass members and films used for packages and the like, and is very useful in industry.

Claims (7)

As the component (A), a dinaphthothiophene compound having one or more polymerizable functional groups having an ethylenically unsaturated double bond represented by the following general formula (1):
(In the general formula (1), each X is independently a single bond, a divalent organic group or a divalent atom, each R ¹ is independently a hydrogen atom or a methyl group, and c + d is C is an integer of 0 to 4 and d is an integer of 0 to 4 on condition that it is an integer of 1 to 4. When X is a divalent organic group, X is an oxygen atom, An alkylene group, an aralkylene group, an alkenylene group, an ester bond, an amide bond, an imide bond, or an alkylene group containing these bonds in the main chain, an arylene group, an aralkylene group, a divalent group that may contain a hetero atom consisting of a sulfur atom or a nitrogen atom A substituted aromatic group, a divalent substituted heteroaromatic group, a divalent substituted silyl group, and when X is a divalent atom, X may be an oxygen atom, a sulfur atom, or another atom. And a tin atom that may have a bond with other atoms A phosphorus atom that may have a bond, wherein X may be bonded to any of the substitutable carbon atoms in the naphthalene ring to which they are bonded, wherein (R) a or (R) b is means a or b identical or different substituents, which may be attached to any of the substitutable carbon atoms in the naphthalene ring to which they are attached, and each R is independently an organic A group, a hydroxyl group, an amino group, a nitro group, a thiol group, a sulfo group, a halogen atom, or an optionally substituted silyl group, a is an integer of 0 to 5, and b is an integer of 0 to 5. (It is an integer.)
(B) As a component, a monofunctional (meth) acrylate containing one or more aromatic rings,
(C) As a component, radical photopolymerization initiator,
The content ratio of the component (A) is in the range of 15 to 50 parts by mass, and the content ratio of the component (B) is in the range of 50 to 85 parts by mass with respect to the total amount of the composition. An adhesive composition for optical parts.   The adhesive composition for optical components according to claim 1, wherein the component (B) is a monofunctional (meth) acrylate containing one aromatic ring.   The adhesive composition for optical components according to claim 1, wherein the component (B) contains one or more selected from benzyl (meth) acrylate and phenoxyethyl (meth) acrylate.   The adhesive composition for optical components according to any one of claims 1 to 3, wherein the polymerizable functional group is a (meth) acryloyl group or an allyl ether group.   In the said General formula (1), it is a = b = c = 0 and is d = 1, The adhesive composition for optical components of any one of Claims 1-4.   The component (A) is one selected from 6-methacryloyloxymethyl dinaphthothiophene, 6-methacryloyloxyethyl dinaphthothiophene, 2,12-diallyloxydinaphthothiophene, and 3,11-diallyloxydinaphthothiophene. The adhesive composition for optical components according to any one of claims 1 to 5, comprising the above. The content ratio of the said (C) component is 0.2-10 mass parts with respect to the total amount of a composition, The adhesive composition for optical components of any one of Claims 1-6.