JP2018151420A - Lens structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lens structure capable of reducing an amount of warpage of a support such as a glass substrate.SOLUTION: A lens structure has a first resin layer 1 having an indentation elastic modulus at room temperature of more than 0 MPa and 3,000 MPa or less and a second resin layer 2 on the first resin layer on a support 4, where the amount of warpage of the support is 0 μm to 50 μm. A resin composition forming the first resin layer 1 contains the following component (a), the following component (b), the following component (C) and/or the following component (d). (a) bifunctional urethane (meth)acrylate compound. (b) photoradical initiator. (c) phenolic antioxidant. (d) phosphite antioxidant.SELECTED DRAWING: Figure 1

Description

The present invention provides a first resin layer having an indentation elastic modulus at room temperature of greater than 0 MPa and less than or equal to 3000 MPa and capable of suppressing warping of a support such as a glass substrate by being laminated as a lower layer film of a second resin layer. And a lens structure having the second resin layer on the support on the first resin layer. In this specification, 23 ° C. is defined as room temperature.

Resin lenses are used in electronic devices such as mobile phones, digital cameras, and in-vehicle cameras, and are required to have excellent optical characteristics according to the purpose of the electronic device. Moreover, high durability, for example, heat resistance and weather resistance, and high productivity that can be molded with a high yield are required in accordance with the usage mode. As a material for a resin lens that satisfies such requirements, for example, a thermoplastic transparent resin such as a polycarbonate resin, a cycloolefin polymer, and a methacrylic resin has been used.

However, injection molding using thermoplastic resin is poor in yield and production efficiency, and wafer level molding by pressing molding using liquid curable resin at room temperature in order to improve the yield and suppress optical axis misalignment during lens lamination. The transition to is being actively studied. In wafer level molding, from the viewpoint of productivity, a hybrid lens system in which a lens is formed on a support such as a glass substrate is generally used.

As a photocurable resin that can be molded at the wafer level, a radically curable resin composition has been conventionally used from the viewpoint of good releasability from a mold, high transparency, and heat yellowing at the time of solder reflow. (Patent Document 1). However, with the recent market demand for thinner camera modules, the thickness of the support used in the hybrid lens system has been reduced. Therefore, when the radical curable resin composition described in Patent Document 1 is used, the problem that a support on which a molded body such as a lens is warped becomes obvious after solder reflow.

As a cause of warping of the support, there is a residual stress generated inside when molding a lens or the like. Therefore, it is necessary to reduce the residual stress in order to reduce the warpage.

Examples of techniques for reducing the warpage of the support include a reduction in the shrinkage rate of the radical curable resin composition and a reduction in the elastic modulus of the cured product in order to reduce stress due to cooling shrinkage. However, there is a limit to the reduction in the shrinkage rate, and it is considered difficult to solve the problem of warping of the support. On the other hand, the elastic modulus of the cured product has a wide range that can be reduced, and is useful for reducing the warpage of the support. Therefore, in patent document 2, curvature is suppressed by setting appropriately the upper limit of the dynamic elastic modulus in 25 degreeC of the hardened | cured material formed by hardening | curing a resin composition. However, when the resin composition described in Patent Document 2 is used, it is necessary to synthesize a urethane acrylate compound suitable as the component (A) of the resin composition, and the versatility is poor.

Japanese Patent No. 5281710 Japanese Patent No. 4783296

The present invention has been made based on the above circumstances, and the problem to be solved is to support a glass substrate or the like even if a resin composition made of a material that is highly versatile and easily available is used. An object of the present invention is to provide a lens structure having a first resin layer that can reduce the amount of warping of the body and has an indentation elastic modulus at room temperature of more than 0 MPa and 3000 MPa or less.

As a result of intensive studies to solve the above-mentioned problems, the inventors of the present invention have provided a first resin layer having an indentation elastic modulus within a predetermined range, and a second resin layer on the first resin layer. The present inventors have found that the amount of warpage of the support is reduced by laminating the support on a support such as a glass substrate, thereby completing the present invention.

That is, the present invention has a first resin layer having an indentation elastic modulus at room temperature of more than 0 MPa and 3000 MPa or less on a support, and a second resin layer on the first resin layer, The amount of warping of the support is a lens structure having 0 to 50 μm. The indentation elastic modulus is preferably greater than 100 MPa and not greater than 2000 MPa. Furthermore, the warp amount of the support is preferably 0 μm to 45 μm.

The support is, for example, a glass substrate.

The resin composition forming the first resin layer is, for example, the following component (a), 0.2 to 5 parts by mass of the following component (b) with respect to 100 parts by mass of the component (a), and the (A) 0.05 parts by weight to 1 part by weight of the following component (c) and / or (a) 100 parts by weight of the component (a) 0.1 parts by weight to 3 parts by weight of the following (d) ) Ingredients.
(A) bifunctional urethane (meth) acrylate compound (b) photo radical initiator (c) phenolic antioxidant (d) phosphite antioxidant

The resin composition forming the first resin layer may further contain 0.1 part by mass to 5 parts by mass of the following component (e) with respect to 100 parts by mass of the component (a).
(E) Adhesive aid

The film thickness of the first resin layer is, for example, 5 μm to 100 μm.

The resin composition forming the second resin layer is, for example, the following (a ′) component, the following (b) component, the following (c) component and / or the following (d) component, and optional components described below ( f) A photocurable composition for imprints containing a component.
(A ′) a di (meth) acrylate compound represented by the following formula (1)
Wherein R ¹ and R ² each independently represent a hydrogen atom or a methyl group, R ³ and R ⁴ each independently represent an alkylene group having 1 to 4 carbon atoms, and R ⁵ and R ⁶ each independently Represents a hydrogen atom or a methyl group, and r ¹ and r ² each independently represents an integer of 1 to 5.)
(B) Photoradical initiator (c) Phenolic antioxidant (d) Phosphite antioxidant (f) Monofunctional or polyfunctional (meth) acrylate compound not containing an aromatic ring (provided that the formula (1) Excluding the di (meth) acrylate compound represented by

The second resin layer is a molded body having a lens shape, for example.

An adhesive layer may be provided between the support and the first resin layer.

In the lens structure of the present invention, a resin composition for forming a second resin layer is formed by laminating a first resin layer having a low elastic modulus on a lower layer of a second resin layer on a support. Even if it is made of a material that is highly versatile and easily available, the amount of warping of the support can be suppressed to 50 μm or less.

Hereinafter, the configuration of the lens structure of the present invention will be described in detail.

<Support>
When a glass substrate is used as the support of the lens structure of the present invention, examples of the glass substrate include soda lime glass, borosilicate glass, alkali-free glass, quartz glass, and sapphire glass. The glass substrate is preferably alkali-free glass that does not substantially contain an alkali metal oxide and is less expensive than quartz glass and sapphire glass, and various commercially available products can be adopted as the alkali-free glass. The thickness of the support is, for example, 0.05 mm to 1.1 mm, preferably 0.1 mm to 0.8 mm.

<First resin layer>
The resin composition forming the first resin layer of the lens structure of the present invention includes the following component (a), the following component (b), the following component (c) and / or the following component (d).
(A) bifunctional urethane (meth) acrylate compound (b) photo radical initiator (c) phenolic antioxidant (d) phosphite antioxidant

[(A) component: bifunctional urethane (meth) acrylate compound]
By using a soft type bifunctional urethane (meth) acrylate compound as the component (a), a first resin layer having a low elastic modulus can be obtained, and the warp of a support such as a glass substrate can be suppressed. It is. Moreover, since the lens structure of the present invention is used for a camera lens, the non-yellowing type of the bifunctional urethane (meth) acrylate compound is suitable.

Specific examples of the component (a) include Aronix [registered trademark] M-1100, M-1200 (above, manufactured by Toagosei Co., Ltd.), UA-4200, UA-4400 (above, Shin-Nakamura Chemical Co., Ltd.) And EBECRYL (registered trademark) 8402, 8804, and 8807 (manufactured by Daicel Ornex Co., Ltd.).

[(B) Component: Photoradical Initiator]
Examples of the photo radical initiator that can be used as the component (b) of the resin composition forming the first resin layer include alkylphenones, benzophenones, Michler's ketones, acylphosphine oxides, and benzoyl. Examples include benzoates, oxime esters, tetramethylthiuram monosulfides, and thioxanthones, and photocleavable photoradical initiators are particularly preferable.

IRGACURE (registered trademark) 184, 369, 651, 500, 819, 907, 784, 2959, CGI 1700, CGI 1750, CGI 1850, CG 24-61, Commercial products such as TPO, 1116, 1173 (above, manufactured by BASF Japan Ltd.), ESACURE KIP150, KIP75 (above, manufactured by Lamberti) and the like can be employed.

The content of the component (b) is 0.2 parts by mass to 5 parts by mass, preferably 0.5 parts by mass to 3 parts by mass with respect to 100 parts by mass of the component (a). When the content of the component (b) is less than 0.2 parts by mass, the strength of the obtained cured product is lowered, and when it is more than 5 parts by mass, the heat-resistant yellowing of the obtained cured product is deteriorated.

[(C) component: phenolic antioxidant]
Examples of the phenolic antioxidant that can be used as the component (c) of the resin composition forming the first resin layer include IRGANOX (registered trademark) 245, 1010, 1035, 1076, and 1135 (and above). , BASF Japan Co., Ltd.), Sumilizer [registered trademark] GA-80, GP, MDP-S, BBM-S, WX-R (above, Sumitomo Chemical Co., Ltd.), and ADK STAB [registered] Trademarks] AO-20, AO-30, AO-40, AO-50, AO-60, AO-80, AO-330 (manufactured by ADEKA Corporation).

Content of the said phenolic antioxidant is 0.05 mass part thru | or 1 mass part with respect to 100 mass parts of said (a) component.

[(D) component: phosphite antioxidant]
Examples of the phosphite-based antioxidant that can be used as the component (d) of the resin composition forming the first resin layer include IRGAFOS (registered trademark) 168 (manufactured by BASF Japan Ltd.) and Adekastab (registered trademark). PEP-36, PEP-8, HP-18, HP-10, HP-10, 2112, 2112RG, 1178, 1500, C, 135A, 3010, TPP (above, ADEKA Corporation) Manufactured).

Content of the said phosphite type | system | group antioxidant is 0.1 mass part thru | or 3 mass parts with respect to 100 mass parts of said (a) component.

In the resin composition forming the first resin layer, either one of the component (c) and the component (d) may be used alone, or both may be used in combination.

[(E) Component: Adhesion aid]
The resin composition forming the first resin layer can also contain an adhesion assistant as the component (e) in order to improve adhesion to a support such as a glass substrate.

Examples of the adhesion assistant usable as the component (e) include a silane coupling agent having a (meth) acryloyloxy group, an amino group, an isocyanate group, or an acid anhydride group as a functional group.

Specific examples of the component (e) include KBM-503, KBM-5103, KBM-903, KBM-9659, X-12-967C (manufactured by Shin-Etsu Chemical Co., Ltd.), Y-9936, A- 174, A-1100, A-1110, A-1310, Y-5187 (above, manufactured by Momentive Performance Materials Japan GK).

The content of the component (e) is 0.1 to 5 parts by mass, preferably 0.5 to 3 parts by mass with respect to 100 parts by mass of the component (a).

The resin composition forming the first resin layer may be diluted with a solvent as necessary.

The solvent is not particularly limited as long as it dissolves the component (a), the component (b), the component (c) and / or the component (d), and the component (e). Examples of such solvents include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate. , Propylene glycol propyl ether acetate, propylene glycol monobutyl ether, propylene glycol monobutyl ether acetate, toluene, xylene, methyl ethyl ketone, cyclopentanone, cyclohexanone, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, ethoxyacetic acid Echi , Ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, ethyl acetate, Mention may be made of butyl acetate, ethyl lactate, butyl lactate, 2-heptanone and γ-butyrolactone. These solvents may be used alone or in combination of two or more.

Among these solvents, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate from the viewpoint of improving leveling properties of a coating film formed by applying the resin composition forming the first resin layer on a support. 2-heptanone, ethyl lactate, butyl lactate, cyclopentanone and cyclohexanone are preferred.

The solid content concentration of the resin composition forming the first resin layer is preferably 50% by mass to 100% by mass (no solvent).

Further, the resin composition forming the first resin layer may contain, as necessary, other additives such as an ultraviolet absorber, a light stabilizer, a leveling agent, a rheology, as long as the effects of the present invention are not impaired. It can contain a regulator, a pigment, a dye, an antifoaming agent, and the like.

The method for preparing the resin composition for forming the first resin layer is not particularly limited. As a preparation method, for example, the component (a), the component (b), the component (c) and / or the component (d), and optionally the component (e) are mixed at a predetermined ratio, If desired, the solvent and other additives may be further added and mixed to obtain a uniform solution.

The cured resin can be obtained by exposing (photocuring) the resin composition forming the first resin layer. Examples of light rays to be exposed include ultraviolet light, electron beams, and X-rays. As a light source used for ultraviolet irradiation, for example, sunlight, a chemical lamp, a low-pressure mercury lamp, a high-pressure mercury lamp, a metal halide lamp, a xenon lamp, and a UV-LED can be used. Moreover, when a solvent is contained, you may pre-bake using heating means, such as a hotplate and oven, before exposure.

The thicker the first resin layer is, the more advantageous it is for reducing warpage, preferably 5 μm to 100 μm, more preferably 10 μm to 70 μm. When the film thickness is too thin, the warp reduction effect cannot be sufficiently obtained, and when it is too thick, it is disadvantageous for thinning the camera module.

<Second resin layer>
The resin composition forming the second resin layer of the lens structure of the present invention is a photo-radical curable resin from the viewpoint of good releasability from a mold, high transparency, and heat-resistant yellowing during solder reflow. The composition is preferably a composition, and includes the following component (a ′), the following component (b), the following component (c) and / or the following component (d), and the following component (f) as an optional component.
(A ′) a di (meth) acrylate compound represented by the following formula (1)
Wherein R ¹ and R ² each independently represent a hydrogen atom or a methyl group, R ³ and R ⁴ each independently represent an alkylene group having 1 to 4 carbon atoms, and R ⁵ and R ⁶ each independently Represents a hydrogen atom or a methyl group, and r ¹ and r ² each independently represents an integer of 1 to 5.)
(B) Photoradical initiator (c) Phenolic antioxidant (d) Phosphite antioxidant (f) Monofunctional or polyfunctional (meth) acrylate compound not containing an aromatic ring (provided that the formula (1) Excluding the di (meth) acrylate compound represented by

[(A ′) component: di (meth) acrylate compound]
The di (meth) acrylate compound that can be used as the component (a ′) has a hydrogenated bisphenol skeleton that does not contain an aromatic ring and is represented by the formula (1). Examples of the di (meth) acrylate compound include ethoxy-modified hydrogenated bisphenol A diacrylate, ethoxy-modified hydrogenated bisphenol A dimethacrylate, propoxy-modified hydrogenated bisphenol A diacrylate, propoxy-modified hydrogenated bisphenol A dimethacrylate, and butoxy-modified water. Bisphenol A diacrylate, butoxy-modified hydrogenated bisphenol A dimethacrylate, ethoxypropoxy-modified hydrogenated bisphenol A diacrylate, ethoxypropoxy-modified hydrogenated bisphenol A dimethacrylate, ethoxy-modified hydrogenated bisphenol F diacrylate, and ethoxy-modified hydrogenated bisphenol Although F dimethacrylate is mentioned, it is not limited to these examples.

Commercially available products such as New Frontier (registered trademark) HBPE-4 and HBPEM-10 (above, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) are employed as the di (meth) acrylate compound represented by the formula (1). be able to.

[Component (b), Component (c), and Component (d)]
As the component (b) of the resin composition forming the second resin layer, a photo radical initiator that can be used as the component (b) of the resin composition forming the first resin layer is employed. The content of the component (b) is, for example, 0.2 to 5 parts by mass, preferably 0.5 to 5 parts by mass with respect to 100 parts by mass of the component (a ′). When the content of the component (b) is less than 0.2 parts by mass, the strength of the obtained cured product is lowered, and when it is more than 5 parts by mass, the heat-resistant yellowing of the obtained cured product is deteriorated. As the component (c) of the resin composition forming the second resin layer, a phenolic antioxidant that can be used as the component (c) of the resin composition forming the first resin layer is employed. The content of the component (c) is, for example, 0.05 part by mass to 2 parts by mass with respect to 100 parts by mass of the component (a ′). As the component (d) of the resin composition forming the second resin layer, a phosphite antioxidant that can be used as the component (d) of the resin composition forming the first resin layer is adopted. . The content of the component (d) is, for example, 0.1 part by mass to 3 parts by mass with respect to 100 parts by mass of the component (a ′). In the resin composition forming the second resin layer, either one of the component (c) and the component (d) may be used alone, or both may be used in combination.

[(F) component: monofunctional or polyfunctional (meth) acrylate compound]
The monofunctional or polyfunctional (meth) acrylate compound that can be used as the component (f) is required not to contain an aromatic ring, and excludes the di (meth) acrylate compound represented by the formula (1). Is. Examples of the monofunctional (meth) acrylate compound include methyl (meth) acrylate, ethyl (meth) acrylate, cyclohexyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, isobornyl (meth) acrylate, norbornyl (meth) acrylate, 1-adamantyl (meth) acrylate, 2-adamantyl (meth) acrylate, 2-methyladamantan-2-yl (meth) acrylate, 2-ethyladamantan-2-yl (meth) acrylate, 1,3-adamantanediol di ( Meth) acrylates, tricyclo [5.2.1.0 ^2,6 ] decanyl (meth) acrylate, and tricyclo [5.2.1.0 ^2,6 ] decan-4-enyl (meth) acrylate. Limited to these examples Is not to be done. Examples of the polyfunctional (meth) acrylate compound include ethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, ethoxylated trimethylolpropane tri (meth) acrylate, ethoxylated glycerin tri (meth) acrylate, and ethoxylated. Pentaerythritol tetra (meth) acrylate, ethoxylated dipentaerythritol hexa (meth) acrylate, polyglycerin monoethylene oxide poly (meth) acrylate, dipentaerythritol hexa (meth) acrylate, neopentyl glycol di (meth) acrylate, pentaerythritol Tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, tricyclodecane dimethanol di (meth) acrylate, , 6-hexanediol di (meth) acrylate, and isocyanuric acid tris (2-acryloyloxyethyl) including without being limited to these examples.

The monofunctional or polyfunctional (meth) acrylate compound may be FANCLIL (registered trademark) FA-511AS, FA-512AS (manufactured by Hitachi Chemical Co., Ltd.), EtADA, EAMA (P), ADA, ADMA, IBXA. , Biscote # 150, # 155, # 200 (above, manufactured by Osaka Organic Chemical Co., Ltd.), NK Ester A-200, A-400, A-600, A-1000, A-9300, A-9300-1CL, UA-53H, 1G, 2G, 3G, 4G, 9G, 14G, 23G, A-GLY-3E, A-GLY-9E, A- GLY-20E, A-TMPT-3EO, A-TMPT-9EO, ATM-4E, ATM-35E, A-DPH, A-TMPT, A-DCP, A-HD-N, AD- MP, same A-DOG, same TMPT, same DCP, same NPG, same HD-N, same D-TMP, NK Oligo U-15HA (manufactured by Shin-Nakamura Chemical Co., Ltd.), KAYARAD (registered trademark) DPEA -12, PEG400DA, THE-330, RP-1040 (above, Nippon Kayaku Co., Ltd.), M-210, M-350, Macromonomer AA-6, AB-6 (above, Toagosei Co., Ltd.) (Commercially available), and commercial products such as KAYARAD (registered trademark) DPHA, NPGDA, and PET30 (manufactured by Nippon Kayaku Co., Ltd.).

The content of the component (f) is, for example, 0 to 110 parts by mass with respect to 100 parts by mass of the component (a ′). That the content of the component (f) is in a range including 0 parts by mass means that the component (f) is not an essential component. When the content of the component (f) is more than 110 parts by mass, the mechanical properties of the cured product obtained from the resin composition forming the second resin layer are deteriorated, and the lens is deformed in the solder reflow process. Occurs or warping of the support increases.

[Other additives]
The resin composition forming the second resin layer is a chain transfer selected from the group consisting of a monofunctional thiol compound, a disulfide compound, and an α-methylstyrene dimer as necessary, as long as the effects of the present invention are not impaired. Agents, ultraviolet absorbers, light stabilizers, leveling agents, rheology modifiers, adhesion aids (silane coupling agents), pigments, dyes, antifoaming agents, and the like.

Examples of the monofunctional thiol compound include methyl mercaptoacetate, methyl 3-mercaptopropionate, 2-ethylhexyl 3-mercaptopropionate, 3-methoxybutyl 3-mercaptopropionate, n-octyl 3-mercaptopropionate, 3- Mercaptocarboxylic esters such as stearyl mercaptopropionate; ethanethiol, 2-methylpropane-2-thiol, n-dodecanethiol, 2,3,3,4,4,5-hexamethylhexane-2-thiol (tert -Dodecanethiol), ethane-1,2-dithiol, propane-1,3-dithiol, alkylthiols such as benzylthiol; benzenethiol, 3-methylbenzenethiol, 4-methylbenzenethiol, naphthalene-2-thiol, Pilisi Aromatic thiols such as 2-thiol, benzimidazol-2-thiol, benzothiazole-2-thiol; mercapto alcohols such as 2-mercaptoethanol, 4-mercapto-1-butanol; and 3- (trimethoxysilyl) And silane-containing thiols such as propane-1-thiol and 3- (triethoxysilyl) propane-1-thiol.

As the monofunctional thiol compound, thiocalcol [registered trademark] 08, 20 (above, manufactured by Kao Corporation), BMPA, MPA-80, EHMP, NOMP, MBMP, STMP (above, manufactured by SC Organic Chemical Co., Ltd.) Commercial products such as KBM-802 and KBM-803 (manufactured by Shin-Etsu Chemical Co., Ltd.) can be used.

Examples of the disulfide compound include diethyl disulfide, dipropyl disulfide, diisopropyl disulfide, dibutyl disulfide, di-tert-butyl disulfide, dipentyl disulfide, diisopentyl disulfide, dihexyl disulfide, dicyclohexyl disulfide, didecyl disulfide, bis (2,3 , 3,4,4,5-hexamethylhexan-2-yl) disulfide (di-tert-dodecyl disulfide), bis (2,2-diethoxyethyl) disulfide, bis (2-hydroxyethyl) disulfide, dibenzyl Alkyl disulfides such as disulfide; diphenyl disulfide, di-p-tolyl disulfide, di (pyridin-2-yl) pyridyl disulfide, di (benzimidazole) Aromatic disulfides such as 2-yl) disulfide and di (benzothiazol-2-yl) disulfide; and thiuram disulfides such as tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetrabutylthiuram disulfide, bis (pentamethylene) thiuram disulfide Kind.

When the resin composition forming the second resin layer contains a chain transfer agent selected from the group consisting of the monofunctional thiol compound, disulfide compound and α-methylstyrene dimer, the content thereof is the above (a) It is 0.1 to 3 parts by mass with respect to 100 parts by mass of the component. When there is more content of the said chain transfer agent than 3 mass%, the mechanical strength of the 2nd resin layer obtained from a resin composition will fall.

When the lens shape is formed on the second resin layer by laminating the first resin layer as a lower layer film of the second resin layer on a support such as a glass substrate, the second resin Residual stress generated inside the layer is relieved, and warpage of the support is reduced. As the resin composition forming the second resin layer, radical curable resin compositions that can be used as lens materials can be widely used.

The resin composition forming the second resin layer can easily produce various molded products in parallel with the formation of the cured product, for example, by using an imprint molding method. As a method for producing a molded body, for example, a step of filling a resin composition for forming the second resin layer in a space between a support and a mold that are in contact with each other, and a resin composition filled in the space The method includes a step of exposing to photocuring, a step of taking out and releasing the obtained photocured product, and a step of heating before, during or after the step of releasing the photocured product. .

The step of exposing and photocuring can be performed by applying conditions for obtaining a cured product from the resin composition forming the first resin layer. Furthermore, the conditions for heating the photocured product are not particularly limited, but are usually appropriately selected from the range of 50 ° C. to 260 ° C. and 1 minute to 24 hours. Moreover, as a heating means, although it does not specifically limit, a hotplate and oven are mentioned. The molded body produced by such a method can be suitably used as a lens for a camera module.
<Adhesive layer>

The lens structure of the present invention has an adhesion layer between the support and the first resin layer by laminating an adhesive layer between the support such as a glass substrate and the first resin layer. Can be improved.

The adhesive layer has the (meth) acryloyloxy group, amino group, isocyanate group, or acid anhydride group as the functional group exemplified as the component (e) of the resin composition forming the first resin layer. A solution obtained by diluting a silane coupling agent with the solvent to 1% by mass can be used.

The lens structure of the present invention will be described with reference to FIGS. In the example shown in FIG. 1, the lens structure of the present invention has a structure in which a first resin layer 1 and a second resin layer 2 are laminated on a support 4 such as a glass substrate.

Further, as in the example shown in FIG. 2, the adhesive layer 3 may be laminated between the support 4 such as a glass substrate and the first resin layer 1 as necessary.

Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples. In the following examples, the apparatus and conditions used for sample preparation and physical property analysis are as follows.
(1) Stirring deaerator: Rotating / revolving mixer manufactured by Shinkey Co., Ltd. Nertaro Awatori [registered trademark] ARE-310
(2) Spin coater: CEE 200X manufactured by Brewer Science
(3) UV exposure device: Batch type UV irradiation device (high pressure mercury lamp 2kW x 1 lamp) manufactured by Eye Graphics Co., Ltd.
(4) Film thickness measuring device: Quick micro MDQ-30 manufactured by Mitutoyo Corporation
(5) Indentation elastic modulus measuring device: Shimadzu Dynamic Ultra Hardness Tester DUH-211 manufactured by Shimadzu Corporation
Indenter: Triangular pyramid indenter (Material: Diamond)
(6) Transmittance measuring device: UV-visible spectrophotometer UV-2600 manufactured by Shimadzu Corporation
Reference: Quartz (7) Warpage measurement device: Non-contact surface texture device PF-60, manufactured by Mitaka Kogyo Co., Ltd.

The suppliers of the compounds used in each example and comparative example are as follows.
M1200: manufactured by Toagosei Co., Ltd. Product name: Aronix [registered trademark] M-1200
EB8402: manufactured by Daicel Ornex Co., Ltd. Product name: EBECRYL [registered trademark] 8402
UA4400: manufactured by Shin-Nakamura Chemical Co., Ltd. Product name: UA-4400
EB4738: manufactured by Daicel Ornex Co., Ltd. Product name: EBECRYL [registered trademark] 4738
KBM5103: Shin-Etsu Chemical Co., Ltd. Product name: KBM-5103
X-12-967C: Shin-Etsu Chemical Co., Ltd. Product name: X-12-967C
HBPE4: manufactured by Daiichi Kogyo Seiyaku Co., Ltd. Brand name: New Frontier [registered trademark] HBPE-4
ADMA: Osaka Organic Chemical Industry Co., Ltd. Product name: ADMA
Product name: Irgacure [registered trademark] 184
I1010: BASF Co., Ltd. Product name: Irganox [registered trademark] 1010
1178: Product made by ADEKA Corporation: Adeka Stub [registered trademark] 1178
DDT: manufactured by Kao Corporation Product name: Thiocalcol [registered trademark] 20

[Preparation of resin composition for forming first resin layer]
<Example 1>
100 parts by mass of M1200 as the component (a), 2 parts by mass of I184 as the component (b), 0.5 parts by mass of I1010 as the component (c), 1 part by mass of 1178 as the component (d), And 1 part by weight of KBM5103 as the component (e) was dissolved in propylene glycol monomethyl ether acetate to prepare an 80% by weight solution (resin composition 1).

<Example 2>
100 parts by mass of EB8402 as the component (a), 2 parts by mass of I184 as the component (b), 0.5 parts by mass of I1010 as the component (c), 1 part by mass of 1178 as the component (d), As a component (e), 1 part by mass of X-12-967C was dissolved in propylene glycol monomethyl ether acetate to prepare a 90% by mass solution (resin composition 2).

<Example 3>
100 parts by mass of UA4400 as the component (a), 2 parts by mass of I184 as the component (b), 0.5 parts by mass of I1010 as the component (c), 1 part by mass of 1178 as the component (d), And 1 mass part of X-12-967C was mixed as said (e) component, and the solvent-free sample (resin composition 3) was prepared.

<Comparative Example 1>
100 parts by mass of EB4738, which is a trifunctional urethane acrylate compound, 2 parts by mass of I184 as the component (b), 0.5 parts by mass of I1010 as the component (c), and 1 part by mass of 1178 as the component (d) As a component (e), 1 part by mass of X-12-967C was dissolved in propylene glycol monomethyl ether acetate to prepare a 90% by mass solution (resin composition 4).

[Preparation of resin composition for forming second resin layer]
<Example 4>
50 parts by mass of HBPE4 as the component (a ′), 50 parts by mass of ADMA as the component (f), 2 parts by mass of I184 as the component (b), and 0.5 parts by mass of I1010 as the component (c) 1 part by weight of 1178 as the component (d) and 1 part by weight of DDT, which is a monofunctional thiol compound as the other additive, are mixed by stirring at 50 ° C. for 3 hours using the stirring deaerator. did. Furthermore, the resin composition which forms a 2nd resin layer was prepared by carrying out stirring deaeration for 10 minutes using the same apparatus.

[Indentation modulus evaluation]
Resin compositions 1 to 4 for forming the first resin layer prepared in Examples 1 to 3 and Comparative Example 1 were each made of glass substrates (MICRO SLIDE manufactured by Matsunami Glass Industry Co., Ltd.) using the spin coater. GLASS S9111, 2.5 cm square, 0.8 mm to 1.0 mm thickness) and prebaked on a hot plate at 60 ° C. for 5 minutes. Next, a first resin layer was produced by UV exposure at 20 mW / cm ² for 300 seconds via an i-line bandpass filter (manufactured by Asahi Spectroscopy) using the UV irradiation apparatus. It was 50 micrometers as a result of measuring the film thickness of the produced 1st resin layer with the said film thickness measuring device.

The indentation elastic modulus of the first resin layer produced by the above method was measured at room temperature using the indentation elastic modulus measuring apparatus according to the following procedure.
(1) Load is applied up to a load of 5 mN at a load speed of 1.46 mN / sec.
(2) After holding for 10 seconds with the maximum load applied, the load is removed.
While changing the measurement position, the above procedures (1) and (2) were repeated, and three points of data were acquired. The average value of the obtained three-point indentation elastic modulus is shown in Table 1 below.

[Evaluation of transmittance and heat yellowing resistance]
Resin compositions 1 to 4 for forming the first resin layer prepared in Examples 1 to 3 and Comparative Example 1 were respectively applied to quartz glass at a rotational speed of 650 rpm to 1200 rpm using the spin coater. And prebaked at 60 ° C. for 5 minutes on a hot plate. Next, the first resin layer having a thickness of 50 μm was produced by UV exposure at 20 mW / cm ² for 300 seconds through the i-line bandpass filter using the UV irradiation apparatus.

The transmittance at a wavelength of 410 nm of the first resin layer produced by the above method was measured using the ultraviolet visible near infrared spectrophotometer. The results are shown in Table 1 below. Further, the first resin layer was heated on a hot plate heated to 260 ° C. for 3 minutes to conduct a heat resistance test. The transmittance at a wavelength of 410 nm of the cured film after the heat resistance test was measured using the ultraviolet-visible-near infrared spectrophotometer, and heat yellowing was evaluated from the transmittance change before and after heating. The results are also shown in Table 1 below.

[Evaluation of warpage]
Resin compositions 1 to 4 for forming the first resin layer prepared in Examples 1 to 3 and Comparative Example 1 were each formed into glass substrates (1.8 cm square, 0.5 mm thickness) using the spin coater. And pre-baked on a hot plate at 60 ° C. for 5 minutes. Next, the first resin layer was produced by performing UV exposure at 20 mW / cm ² through the i-line bandpass filter for 300 seconds using the UV irradiation apparatus.

Furthermore, 0.040 g of the resin composition forming the second resin layer prepared in Example 4 was subjected to mold release treatment by applying NOVEC [registered trademark] 1720 (manufactured by 3M Japan) and drying. Weighed on the substrate. Thereafter, the resin was sandwiched between the first resin layers produced on the glass substrate through a 500 μm thick silicone rubber spacer. Next, the resin composition for forming the second resin layer was subjected to UV exposure at 20 mW / cm ² for 300 seconds through the i-line bandpass filter using the UV irradiation device. The cured product obtained after the exposure is peeled off from the release-treated glass substrate, and then heated on a hot plate at 150 ° C. for 20 minutes, whereby the diameter is formed on the first resin layer produced on the glass substrate. A second resin layer having a thickness of 1.0 cm, a thickness of 0.5 mm, and a mass of 0.040 g was produced.

<Comparative Example 2>
In this comparative example, the first resin layer is not manufactured. On a glass substrate subjected to mold release treatment by applying 0.040 g of the resin composition forming the second resin layer prepared in Example 4 to NOVEC [registered trademark] 1720 (manufactured by 3M Japan) and drying. Weighed out. Thereafter, a glass substrate (1.8 cm square, 0.00 mm square, 0.005 cm, 0.005 mm) coated with a solution obtained by diluting KBM-5103 with propylene glycol monomethyl ether acetate to 1% by mass through a 500 μm thick silicone rubber spacer was dried. 5 mm thick). Next, the resin composition for forming the second resin layer was subjected to UV exposure at 20 mW / cm ² for 300 seconds through the i-line bandpass filter using the UV irradiation device. The cured product obtained after the exposure is peeled off from the release-treated glass substrate, and then heated on a hot plate at 150 ° C. for 20 minutes, thereby having a diameter of 1.0 cm and a thickness on the adhesion-treated glass substrate. A second resin layer having a thickness of 0.5 mm and a mass of 0.04 g was produced.

The glass substrate on which the second resin layer was produced was disposed on the stage of the non-contact surface texture measuring device so that the glass substrate became the upper surface. Using the center of the glass substrate as the measurement start point, displacement in the direction perpendicular to the stage (Z axis) was measured toward the four apexes of the glass substrate. From the measurement data, the amount of displacement in the vertical direction (Z-axis) between the center of the glass substrate and each vertex of the glass substrate was calculated, and the average value thereof was defined as the amount of warpage. FIG. 3 schematically shows a method for evaluating the amount of warpage of the glass substrate. The glass substrate after the measurement was subjected to a heat resistance test by heating it on a hot plate at 260 ° C. for 3 minutes, and then measured again by the above method to evaluate the amount of warpage. The respective results are also shown in Table 1 below.

As shown in Table 1, the first resin layer produced from the resin compositions 1 to 3 prepared in Examples 1 to 3 has a sufficiently low indentation elastic modulus, which is advantageous for reducing the warpage amount of the glass substrate. It is. Moreover, it turned out that the said 1st resin layer has the favorable transmittance | permeability before and behind a heat resistance test, and heat yellowing resistance.

Furthermore, the structure of the present invention having the first resin layer prepared from the resin compositions 1 to 3 prepared in Examples 1 to 3 was prepared from the resin composition 4 prepared in Comparative Example 1. It was confirmed that the amount of warpage of the glass substrate before and after the heat resistance test was reduced to less than half compared to the structure having the first resin layer and Comparative Example 2 not having the first resin layer. . That is, by laminating the first resin layer produced from the resin composition 1 to the resin composition 3 as the lower layer film of the second resin layer, the warpage amount of the glass substrate as the support can be greatly reduced. Indicated.

FIG. 1 is a schematic view of a lens structure of the present invention in which a first resin layer and a second resin layer are laminated on a first support layer such as a glass substrate. FIG. 2 is a schematic view of the lens structure of the present invention in which a first resin layer and a second resin layer are laminated on a support such as a glass substrate via an adhesive layer. FIG. 3 is a schematic diagram showing a method for evaluating the amount of warpage of the glass substrate.

1: First resin layer 2: Second resin layer 3: Adhesive layer 4: Support such as glass substrate

Claims (8)

The support has a first resin layer having an indentation elastic modulus at room temperature of greater than 0 MPa and less than or equal to 3000 MPa, and a second resin layer on the first resin layer, and the amount of warpage of the support is A lens structure that is 0 μm to 50 μm. The lens structure according to claim 1, wherein the support is a glass substrate. The resin composition forming the first resin layer comprises the following component (a), 0.2 to 5 parts by mass of the following component (b) with respect to 100 parts by mass of the component (a), and the (a) ) 0.05 parts by mass to 1 part by mass of the following component (c) and / or 0.1 parts by mass to 3 parts by mass of the following component (d) The lens structure according to claim 1 or 2, comprising:
(A) bifunctional urethane (meth) acrylate compound (b) photo radical initiator (c) phenolic antioxidant (d) phosphite antioxidant The resin composition which forms the said 1st resin layer further contains 0.1 mass part thru | or 5 mass parts of the following (e) component with respect to 100 mass parts of said (a) component. Lens structure.
(E) Adhesive aid The lens structure according to claim 1, wherein the first resin layer has a thickness of 5 μm to 100 μm. The resin composition forming the second resin layer includes the following component (a ′), the following component (b), the following component (c) and / or the following component (d), and the following optional component (f): The lens structure according to any one of claims 1 to 5, which is a photocurable composition for imprints containing a component.
(A ′) a di (meth) acrylate compound represented by the following formula (1)
Wherein R ¹ and R ² each independently represent a hydrogen atom or a methyl group, R ³ and R ⁴ each independently represent an alkylene group having 1 to 4 carbon atoms, and R ⁵ and R ⁶ each independently Represents a hydrogen atom or a methyl group, and r ¹ and r ² each independently represents an integer of 1 to 5.)
(B) Photoradical initiator (c) Phenolic antioxidant (d) Phosphite antioxidant (f) Monofunctional or polyfunctional (meth) acrylate compound not containing an aromatic ring (provided that the formula (1) Excluding the di (meth) acrylate compound represented by The lens structure according to any one of claims 1 to 6, wherein the second resin layer is a molded body having a lens shape. The lens structure according to any one of claims 1 to 7, further comprising an adhesive layer between the support and the first resin layer.