JP6936449B2 - Thermosetting resin composition - Google Patents

Description

The present invention is used for producing a high refractive index flattening film and producing a high refractive index microlens containing a self-crosslinking copolymer, an ultraviolet absorber having at least one triazine ring in one molecule, and an organic solvent. It relates to a possible thermosetting resin composition.

In recent years, in the field of electronic devices such as liquid crystal displays, organic EL displays, light emitting diodes, solar cells, and CCD / CMOS image sensors, protective films, flattening films, insulating films, antireflection films, refractive index control films, microlenses, etc. Resin compositions using a polymer material having excellent transparency in the visible light region are often used for optical members such as intra-layer lenses, optical waveguides, and film substrates. Such an optical member is required not only to have transparency but also to have excellent heat resistance and light resistance. Further, the optical member is often required to have a high refractive index in order to improve the light extraction efficiency and the light collecting property.

Generally, as a method for increasing the refractive index of a polymer material, for example, an aromatic ring, a halogen atom other than a fluorine atom, a sulfur atom, a metal atom, or a hydrogen bond can be introduced into the molecule of the polymer material. It is used. Regarding the introduction of aromatic rings, the introduction of fused cyclic hydrocarbon groups such as naphthalene ring and anthracene ring is more effective means for increasing the refractive index of polymer materials than monocyclic hydrocarbon groups such as phenyl group. (Patent Document 1 and Patent Document 2).

Further, the etchback method is known as one of the methods for manufacturing a microlens for a CCD / CMOS image sensor (Patent Documents 3 and 4). That is, a resist pattern is formed on the resin layer for a microlens formed on the color filter layer, and the resist pattern is reflowed by heat treatment to form a lens pattern. Using the lens pattern formed by reflowing this resist pattern as an etching mask, the lower resin layer for microlenses is etched back, and the shape of the lens pattern is transferred to the resin layer for microlenses to produce a microlens. In the etchback method, when the lens pattern shape is faithfully transferred to the lower resin layer for microlenses, the dry etching rate X of the resist pattern and the dry etching rate Y of the resin layer for microlenses are equivalent (X: Y = 1: 1). 0.8 to 1.2) is required (Patent Document 5).

Japanese Unexamined Patent Publication No. 8-53517 International Publication No. 2008/143095 Japanese Unexamined Patent Publication No. 1-1066 Japanese Unexamined Patent Publication No. 6-112459 International Publication No. 2013/005619

When a condensed ring hydrocarbon group is introduced into the molecule of the polymer material, the polymer material tends to be deteriorated by light such as ultraviolet rays because the absorption wavelength becomes longer. Therefore, an optical member manufactured by using a resin composition using a polymer material into which a fused cyclic hydrocarbon group has been introduced is likely to cause quality deterioration such as discoloration, and thus has a high refractive index and high light resistance. There was a problem that it became difficult to achieve both.

The present invention has been made based on the above circumstances, and an object of the present invention is to have a high refractive index and excellent transparency, heat resistance, light resistance, solvent resistance, flatness and dryness equivalent to that of a resist. It is an object of the present invention to provide a thermosetting resin composition capable of forming a cured film having an etching rate. Another object of the present invention is to provide a flattening film and a microlens having a high refractive index and excellent transparency, heat resistance, light resistance and solvent resistance.

［式（１）乃至式（３）中、Ａｒは縮合環式炭化水素基を表し、Ｒ^１及びＲ^２はそれぞれ独立に水素原子又はメチル基を表し、Ｒ^３は単結合又はアルキレン基を表し、Ａ^１はオキシラン環を有する基を表し、Ｒ^４はアルキル基を表し、Ａ^２はアルコキシ基を表す。］The present inventors have completed the present invention as a result of diligent studies to solve the above-mentioned problems. That is, the present invention is a self-crosslinkable copolymer having a structural unit represented by the following formula (1), a structural unit represented by the following formula (2), and a structural unit represented by the following formula (3). A thermosetting resin containing a triazine-based ultraviolet absorber and an organic solvent, wherein the triazine-based ultraviolet absorber is contained in a proportion of 3% by mass to 20% by mass with respect to the content of the self-crosslinking copolymer. It is a composition.

[In formulas (1) to (3), Ar represents a fused ring hydrocarbon group, R ¹ and R ² each independently represent a hydrogen atom or a methyl group, and R ³ represents a single bond or an alkylene group. , A ¹ represents a group having an oxylan ring, R ⁴ represents an alkyl group, and A ² represents an alkoxy group. ]

The fused cyclic hydrocarbon group is, for example, a naphthyl group, and the group having an oxylan ring is, for example, an epoxy group.

The self-crosslinkable copolymer contains, for example, at least 70 mol% of the structural unit represented by the formula (1). The self-crosslinkable copolymer has, for example, a weight average molecular weight of 6,000 to 25,000.

（式中、＊は前記トリアジン環の炭素原子との結合手を表し、Ａ^３及びＡ^４はそれぞれ独立に水素原子又は有機基を表す。）The triazine-based ultraviolet absorber is a compound containing a triazine ring and three phenyl groups bonded to a carbon atom of the triazine ring, which may have a substituent, and at least one of the three phenyl groups. Is a group represented by the following formula (4).

(Wherein, * represents a bond to the carbon atom of the triazine ring, A ³ and A ⁴ each independently represent a hydrogen atom or an organic group.)

The thermosetting resin composition of the present invention may further contain a surfactant.

The thermosetting resin composition of the present invention is, for example, a resin composition for a flattening film or a resin composition for a microlens.

Since the copolymer contained in the composition is a self-crosslinking type, the thermosetting resin composition of the present invention does not necessarily require the addition of a cross-linking agent and has thermosetting properties. Further, the thermosetting resin composition of the present invention is excellent in storage stability because the carboxyl group is blocked (protected) in the structural unit represented by the formula (3) of the copolymer. Further, the cured film formed from the thermosetting resin composition of the present invention has a high refractive index (1.65 or more), excellent transparency, heat resistance, solvent resistance, flatness, and etching equivalent to that of a resist pattern. Have a rate. Therefore, the thermosetting resin composition of the present invention is suitable as a material for forming a microlens and a flattening film.

FIG. 1 is a schematic view showing a cured film formed by applying the resin composition of the present invention on a stepped substrate and baking it.

Hereinafter, each component of the thermosetting resin composition of the present invention will be described in detail. In the thermosetting resin composition of the present invention, the content of the solid content defined as all the components excluding the solvent from the composition is usually 1% by mass to 50% by mass. In this specification, even a liquid component is treated as a "solid content" for convenience.

<Self-crosslinkable copolymer>
The self-crosslinkable copolymer contained in the thermosetting resin composition of the present invention is a copolymer having structural units represented by the above-mentioned formulas (1), (2) and (3).

Specific examples of the compound (monomer) forming the structural unit represented by the formula (1) include 1-vinylnaphthalene, 2-vinylnaphthalene, 6-methyl-2-vinylnaphthalene, and 5,8-dimethyl-2. -Vinylnaphthalene, 6-methoxy-2-vinylnaphthalene, 5,8-dimethoxy-2-vinylnaphthalene, 6-hydroxy-2-vinylnaphthalene, 5,8-dihydroxy-2-vinylnaphthalene, 6-bromo-2- Examples thereof include vinylnaphthalene, 5,8-dibromo-2-vinylnaphthalene, 1-vinylanthracene, 2-vinylanthracene, 9-vinylanthracene and N-vinylcarbazole. These compounds may be used alone or in combination of two or more.

Specific examples of the compound (monomer) forming the structural unit represented by the formula (2) include glycidyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate glycidyl ether, and 3,4-epoxycyclopentylmethyl (meth). ) Acrylate, 3,4-epoxycyclohexylmethyl (meth) acrylate, 5,6-epoxy-2-bicyclo [2.2.1] heptylmethyl (meth) acrylate, 3,4-epoxytricyclo [5.2. 1.0 ^2,6 ] Decane-8-yl (meth) acrylate can be mentioned. These monomers may be used alone or in combination of two or more. In addition, the description such as (meth) acrylate and (meth) acrylic acid in this specification represents both methacrylate and acrylate, and methacrylic acid and acrylic acid.

The compound (monomer) forming the structural unit represented by the formula (3) is obtained as an acrylate or methacrylate having a protected carboxyl group by reacting acrylic acid or methacrylic acid with an alkenyl ether compound. Instead of the above method, the structural unit represented by the above formula (3) can also be formed by a method of reacting an alkenyl ether compound with a structural unit obtained by (co) polymerizing acrylic acid or methacrylic acid.

（式中、Ｒ^５は水素原子又は炭素原子数１乃至１０のアルキル基を表し、Ｒ^６は炭素原子数１乃至１０のアルキル基又は炭素原子数６乃至１０の環状炭化水素基を表す。）The alkenyl ether compound is represented by the following formula (5).

(In the formula, R ⁵ represents a hydrogen atom or an alkyl group ^{having 1 to 10 carbon atoms, and R 6} represents an alkyl group having 1 to 10 carbon atoms or a cyclic hydrocarbon group having 6 to 10 carbon atoms.)

The reaction between the compound having a carboxyl group and the alkenyl ether compound is stirred at 70 ° C. using, for example, monooctyl phosphate, which is one of the phosphoric acid esters, as described in Japanese Patent No. 3042033. It can be done by.

Examples of the alkenyl ether compound represented by the formula (5) include methyl vinyl ether, ethyl vinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl ether, tert-butyl vinyl ether, n-hexyl vinyl ether, cyclohexyl vinyl ether, and 2 -Ethyl hexyl vinyl ether can be mentioned.

（式中、Ｒ^２は水素原子又はメチル基を表し、Ｒ^６は炭素原子数１乃至１０のアルキル基又は炭素原子数６乃至１０の環状炭化水素基を表す。） The structural unit represented by the formula (3) is represented by, for example, the following formula (3-1).

(In the formula, R ² represents a hydrogen atom or a methyl group, and R ⁶ represents an alkyl group having 1 to 10 carbon atoms or a cyclic hydrocarbon group having 6 to 10 carbon atoms.)

Specific examples of the compound (monomer) forming the structural unit represented by the formula (3) include 1-methoxyethyl (meth) acrylate, 1-ethoxyethyl (meth) acrylate, and 1-propoxyethyl (meth) acrylate. , 1-Isopropoxyethyl (meth) acrylate, 1-n-butoxyethyl (meth) acrylate, 1-tert-butoxyethyl (meth) acrylate, 1-n-hexyloxyethyl (meth) acrylate, 1-cyclohexyloxyethyl Examples include (meth) acrylate. These monomers may be used alone or in combination of two or more.

In a self-crosslinkable copolymer having structural units represented by the formulas (1), (2) and (3), the structural units represented by the formula (1) are represented by the formula (2). The content of the structural unit represented by the formula (1) is 60 mol% to 95 mol%, preferably 70 mol%, based on 100 mol% of the sum of the structural unit to be crosslinked and the structural unit represented by the formula (3). The content of the structural unit represented by the formula (2) is 2 mol% to 20 mol%, preferably 5 mol% to 15 mol%, and the content of the structural unit represented by the formula (3) is. It is 2 mol% to 30 mol%, preferably 5 mol% to 15 mol%.

The weight average molecular weight of the self-crosslinking copolymer is usually 1,000 to 100,000, preferably 6,000 to 25,000, and more preferably 6,000 to 20,000. The weight average molecular weight is a value obtained by gel permeation chromatography (GPC) using polystyrene as a standard sample.

The content of the self-crosslinkable copolymer in the thermosetting resin composition of the present invention is usually 50% by mass to 99% by mass based on the solid content of the thermosetting resin composition. Yes, preferably 70% by mass to 95% by mass.

In the present invention, the method for obtaining the self-crosslinkable copolymer is not particularly limited, but in general, the compound forming the structural unit represented by the formulas (1), (2) and (3). A polymerization reaction of (monomer) and, if desired, a compound other than the above compound (hereinafter, abbreviated as Compound X in the present specification) in a solvent in the presence of a polymerization initiator, usually at a temperature of 50 ° C. to 120 ° C. It is obtained by letting it. The copolymer thus obtained is usually in a solution state dissolved in a solvent, and can be used in the thermosetting resin composition of the present invention without being isolated in this state.

Further, the solution of the self-crosslinkable copolymer obtained as described above is put into a poor solvent such as agitated diethyl ether, toluene, methanol, ethanol, isopropanol, acetonitrile or water to obtain the copolymer. The copolymer is made into an oil or powder by reprecipitation, decantation or filtration of the produced precipitate, washing as necessary, and then drying at room temperature or heating under normal pressure or reduced pressure. be able to. By such an operation, the polymerization initiator and the unreacted compound coexisting with the copolymer can be removed. In the present invention, the oily substance or powder of the copolymer may be used as it is, or the oily substance or powder may be redissolved in a solvent described later and used as a solution.

Specific examples of the compound X include styrene, 4-vinylbiphenyl, 2-vinylfluorene, acenaphthylene, (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, and cyclohexyl (meth). ) Acrylate, isobornyl (meth) acrylate, adamantyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, benzyl (meth) acrylate, γ- Butyrolactone (meth) acrylate, inden, maleimide, N-methylmaleimide, N-ethylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide, N-benzylmaleimide, N- (4-hydroxyphenyl) maleimide, 2-hydroxyethylvinyl ether , 3-Hydroxypropyl vinyl ether, 4-hydroxybutyl vinyl ether, 5-hydroxypentyl vinyl ether, 6-hydroxyhexyl vinyl ether, 4-hydroxycyclohexyl vinyl ether, 1,4-cyclohexanedimethanol monovinyl ether, diethylene glycol monovinyl ether and dipropylene glycol monovinyl ether. Can be mentioned.

<Triazine-based UV absorber>
Examples of the triazine-based ultraviolet absorber contained in the thermosetting resin composition of the present invention include compounds represented by the following formulas (T-1) to (T-15).

Examples of commercially available products of the triazine-based ultraviolet absorber include Tinuvin (registered trademark) 400, 405, 460, 477, 479, 1577ED, 1600 (above, manufactured by BASF Japan Ltd.), and ADEKA STAB. [Registered trademark] LA-46, LA-F70 (all manufactured by ADEKA Corporation), KEMISORB [Registered trademark] 102 (manufactured by Chemipro Kasei Co., Ltd.) can be mentioned. These triazine-based ultraviolet absorbers may be used alone or in combination of two or more.

The content of the triazine-based ultraviolet absorber contained in the thermosetting resin composition of the present invention is preferably 3% by mass to 20% by mass, more preferably 5% by mass, based on the content of the self-crosslinkable copolymer. % To 20% by mass.

The method for preparing the thermosetting resin composition of the present invention is not particularly limited, but for example, a self-crosslinkable copolymer having structural units represented by the formulas (1), (2) and (3). Is dissolved in an organic solvent described later, and the triazine-based ultraviolet absorber is mixed with the obtained solution at a predetermined ratio to obtain a uniform solution. Further, at an appropriate stage of this preparation method, a method of further adding and mixing other additives, if necessary, can be mentioned.

<Organic solvent>
The organic solvent contained in the thermosetting resin composition of the present invention is not particularly limited as long as it dissolves the self-crosslinking copolymer and the triazine-based ultraviolet absorber contained in the thermosetting resin composition. .. Examples of such organic 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, and propylene glycol monomethyl ether. Acetate, propylene glycol monoethyl ether, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether, 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, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, Ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, ethyl acetate, butyl acetate, ethyl lactate, butyl lactate, 2-heptanone, γ-butyrolactone, N, N-dimethylacetamide, N-methyl-2 -Pyrrolidone and N-ethyl-2-pyrrolidone can be mentioned. These organic solvents may be used alone or in combination of two or more.

Among the above organic solvents, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, and propylene glycol mono from the viewpoint of improving the leveling property of the coating film formed by applying the thermosetting resin composition of the present invention on the substrate. Ethyl ether, propylene glycol monopropyl ether, 2-heptanone, ethyl lactate, butyl lactate, methyl pyruvate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, cyclopentanone, cyclohexanone, N, N-dimethylacetamide, N-methyl-2-pyrrolidone and γ-butyrolactone are preferred.

<Surfactant>
Further, the thermosetting resin composition of the present invention may also contain a surfactant for the purpose of improving coatability. Examples of the surfactant include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, and polyoxyethylene oleyl ether, polyoxyethylene octylphenyl ether, and polyoxy. Polyoxyethylene alkylaryl ethers such as ethylene nonylphenyl ether, polyoxyethylene / polyoxypropylene block copolymers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, sorbitan Solbitan fatty acid esters such as tristearate, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, polyoxyethylene sorbitan tristearate, etc. Nonionic surfactants such as polyoxyethylene sorbitan fatty acid esters, Ftop [registered trademark] EF301, EF303, EF352 (all manufactured by Mitsubishi Materials Denshi Kasei Co., Ltd.), Megafuck [registered trademark] F171, same F173, R-30, R-40, R-40-LM (above, manufactured by DIC Co., Ltd.), Florard FC430, FC431 (above, manufactured by Sumitomo 3M Co., Ltd.), Asahi Guard [registered trademark] AG710, Surfron (registered trademark) S-382, SC101, SC102, SC103, SC104, SC105, SC106 (manufactured by AGC Co., Ltd.), DFX-18, FTX-206D, FTX-212D, FTX- 218, FTX-220D, FTX-230D, FTX-240D, FTX-212P, FTX-220P, FTX-228P, FTX-240G, etc. Fluorine surfactants such as Futergent series (manufactured by Neos Co., Ltd.), organosiloxane Polymer KP341 (manufactured by Shin-Etsu Chemical Industry Co., Ltd.) can be mentioned. These surfactants can be used alone or in combination of two or more.

When the surfactant is used, the content in the thermosetting resin composition of the present invention is usually 0.0001% by mass to 3% by mass based on the solid content of the resin composition. It is preferably 0.001% by mass to 1% by mass, and more preferably 0.01% by mass to 0.5% by mass.

Further, the thermosetting resin composition of the present invention can be used as a curing agent, a curing aid, a sensitizer, a plasticizer, an antioxidant, a light stabilizer, as necessary, as long as the effects of the present invention are not impaired. HALS), additives such as adhesion aids can be included.

Hereinafter, the use of the thermosetting resin composition of the present invention will be described.
<Method of producing cured film>
A method for producing a cured film using the thermosetting resin composition of the present invention will be described. Suitable spinners, coaters, etc. on a substrate (for example, PET film, TAC film, semiconductor substrate, glass substrate, quartz substrate, silicon wafer, and a substrate on which various metal films or color filters are formed on the surface of these). After applying the thermosetting resin composition of the present invention by a coating method, a cured film is prepared by baking using a heating means such as a hot plate or an oven. The baking conditions are appropriately selected from a baking temperature of 50 ° C. to 300 ° C. and a baking time of 0.1 minutes to 360 minutes. The bake at the time of preparing the cured film may be treated in two or more steps. The film thickness of the cured film formed from the thermosetting resin composition of the present invention is, for example, 0.001 μm to 1000 μm, preferably 0.01 μm to 100 μm, and more preferably 0.1 μm to 10 μm. Is.

<How to make a microlens>
A method for producing a microlens using the thermosetting resin composition of the present invention will be described. A resist is applied onto the cured film produced through the method for producing a cured film, the resist is exposed through a predetermined mask, and if necessary, post-exposure heating (PEB) is performed, and then alkali development, rinsing, and so on. And by drying, a predetermined resist pattern is formed on the cured film. For the exposure, for example, g-line, i-line, KrF excimer laser, and ArF excimer laser can be used. Then, by heat treatment, the resist pattern is reflowed to form a lens pattern. Using this lens pattern as an etching mask, the cured film underneath the lens pattern is etched back, and the shape of the lens pattern is transferred to the cured film to produce a microlens.

The present invention will be described in more detail below based on Examples and Comparative Examples, but the present invention is not limited to these Examples.
[Measurement of weight average molecular weight of copolymer obtained in the following synthesis example]
Equipment: JASCO Corporation GPC system Column: Shodex® GPC KF-804L and GPC KF-803L
Column oven: 40 ° C
Flow rate: 1 mL / min Eluent: tetrahydrofuran

[Synthesis of self-crosslinkable copolymer]
<Synthesis example 1>
15.0 g of 2-vinylnaphthalene, 3.9 g of 1-n-butoxyethyl methacrylate, 3.0 g of glycidyl methacrylate, and 1.5 g of 2,2'-azobisisobutyronitrile in 23.3 g of propylene glycol monomethyl ether acetate. It was dissolved. The obtained solution was added dropwise to a flask in which 31.1 g of propylene glycol monomethyl ether acetate was held at 70 ° C. over 4 hours. After completion of the dropping, the reaction was carried out for 18 hours to obtain a solution of the copolymer (solid content concentration: 30% by mass). The weight average molecular weight Mw of the obtained copolymer was 6,000 (in terms of polystyrene).

<Synthesis example 2>
18.0 g of 2-vinylnaphthalene, 2.7 g of 1-n-butoxyethyl methacrylate, 2.1 g of glycidyl methacrylate, and 0.7 g of 2,2'-azobisisobutyronitrile in 23.5 g of propylene glycol monomethyl ether acetate. It was dissolved. The obtained solution was added dropwise to a flask in which 31.4 g of propylene glycol monomethyl ether acetate was maintained at 70 ° C. over 4 hours. After completion of the dropping, the reaction was carried out for 18 hours to obtain a solution of the copolymer (solid content concentration: 30% by mass). The weight average molecular weight Mw of the obtained copolymer was 16,000 (in terms of polystyrene).

<Synthesis example 3>
20.0 g of 2-vinylnaphthalene, 1.4 g of 1-n-butoxyethyl methacrylate, 1.1 g of glycidyl methacrylate, and 0.5 g of 2,2'-azobisisobutyronitrile to 23.5 g of propylene glycol monomethyl ether acetate. After dissolution, the obtained solution was added dropwise to a flask in which 31.4 g of propylene glycol monomethyl ether acetate was maintained at 70 ° C. over 4 hours. After completion of the dropping, the reaction was carried out for 18 hours to obtain a solution of the copolymer (solid content concentration: 30% by mass). The weight average molecular weight Mw of the obtained copolymer was 20,000 (in terms of polystyrene).

[Preparation of thermosetting resin composition]
<Example 1>
20.0 g of the copolymer solution obtained in Synthesis Example 1, 0.3 g of a triazine-based ultraviolet absorber compound represented by the above formula (T-9), and Megafuck (registered trademark) R as a surfactant. A solution was obtained by dissolving 0.003 g of -40 (manufactured by DIC Co., Ltd.) in 7.4 g of propylene glycol monomethyl ether acetate and 14.3 g of cyclohexanone. Then, the obtained solution was filtered using a polyethylene microfilter having a pore size of 0.10 μm to prepare a thermosetting resin composition.

<Example 2>
20.0 g of the copolymer solution obtained in Synthesis Example 2, 0.3 g of a triazine-based ultraviolet absorber compound represented by the above formula (T-9), and Megafuck (registered trademark) R as a surfactant. A solution was obtained by dissolving 0.003 g of -40 (manufactured by DIC Co., Ltd.) in 7.4 g of propylene glycol monomethyl ether acetate and 14.3 g of cyclohexanone. Then, the obtained solution was filtered using a polyethylene microfilter having a pore size of 0.10 μm to prepare a thermosetting resin composition.

<Example 3>
20.0 g of the copolymer solution obtained in Synthesis Example 3, 0.3 g of a triazine-based ultraviolet absorber compound represented by the above formula (T-9), and Megafuck (registered trademark) R as a surfactant. A solution was obtained by dissolving 0.003 g of -40 (manufactured by DIC Co., Ltd.) in 7.4 g of propylene glycol monomethyl ether acetate and 14.3 g of cyclohexanone. Then, the obtained solution was filtered using a polyethylene microfilter having a pore size of 0.10 μm to prepare a thermosetting resin composition.

<Example 4>
20.0 g of the copolymer solution obtained in Synthesis Example 1, 0.18 g of a triazine-based ultraviolet absorber compound represented by the above formula (T-9), and Megafuck (registered trademark) R as a surfactant. A solution was obtained by dissolving 0.003 g of -40 (manufactured by DIC Co., Ltd.) in 7.0 g of propylene glycol monomethyl ether acetate and 14.0 g of cyclohexanone. Then, the obtained solution was filtered using a polyethylene microfilter having a pore size of 0.10 μm to prepare a thermosetting resin composition.

<Example 5>
20.0 g of the copolymer solution obtained in Synthesis Example 1, 0.6 g of the compound represented by the above formula (T-9), which is a triazine-based ultraviolet absorber, and Megafuck [registered trademark] R as a surfactant. A solution was obtained by dissolving 0.003 g of -40 (manufactured by DIC Co., Ltd.) in 5.3 g of propylene glycol monomethyl ether acetate and 12.9 g of cyclohexanone. Then, the obtained solution was filtered using a polyethylene microfilter having a pore size of 0.10 μm to prepare a thermosetting resin composition.

<Example 6>
20.0 g of the copolymer solution obtained in Synthesis Example 1, 1.2 g of a triazine-based ultraviolet absorber compound represented by the above formula (T-9), and Megafuck [registered trademark] R as a surfactant. A solution was obtained by dissolving 0.003 g of -40 (manufactured by DIC Co., Ltd.) in 3.3 g of propylene glycol monomethyl ether acetate and 11.5 g of cyclohexanone. Then, the obtained solution was filtered using a polyethylene microfilter having a pore size of 0.10 μm to prepare a thermosetting resin composition.

<Example 7>
20.0 g of the copolymer solution obtained in Synthesis Example 2, 0.3 g of a triazine-based ultraviolet absorber compound represented by the above formula (T-7), and Megafuck (registered trademark) R as a surfactant. A solution was obtained by dissolving 0.003 g of -40 (manufactured by DIC Co., Ltd.) in 7.4 g of propylene glycol monomethyl ether acetate and 14.3 g of cyclohexanone. Then, the obtained solution was filtered using a polyethylene microfilter having a pore size of 0.10 μm to prepare a thermosetting resin composition.

<Example 8>
20.0 g of the copolymer solution obtained in Synthesis Example 2, 0.3 g of a triazine-based ultraviolet absorber compound represented by the above formula (T-6), and Megafuck (registered trademark) R as a surfactant. A solution was obtained by dissolving 0.003 g of -40 (manufactured by DIC Co., Ltd.) in 7.4 g of propylene glycol monomethyl ether acetate and 14.3 g of cyclohexanone. Then, the obtained solution was filtered using a polyethylene microfilter having a pore size of 0.10 μm to prepare a thermosetting resin composition.

<Example 9>
20.0 g of the copolymer solution obtained in Synthesis Example 2, 0.3 g of a triazine-based ultraviolet absorber compound represented by the above formula (T-11), and Megafuck (registered trademark) R as a surfactant. A solution was obtained by dissolving 0.003 g of -40 (manufactured by DIC Co., Ltd.) in 7.4 g of propylene glycol monomethyl ether acetate and 14.3 g of cyclohexanone. Then, the obtained solution was filtered using a polyethylene microfilter having a pore size of 0.10 μm to prepare a thermosetting resin composition.

<Example 10>
20.0 g of the copolymer solution obtained in Synthesis Example 2, 0.3 g of a triazine-based ultraviolet absorber compound represented by the above formula (T-13), and Megafuck (registered trademark) R as a surfactant. A solution was obtained by dissolving 0.003 g of -40 (manufactured by DIC Co., Ltd.) in 7.4 g of propylene glycol monomethyl ether acetate and 14.3 g of cyclohexanone. Then, the obtained solution was filtered using a polyethylene microfilter having a pore size of 0.10 μm to prepare a thermosetting resin composition.

<Example 11>
20.0 g of the copolymer solution obtained in Synthesis Example 2, 0.3 g of a triazine-based ultraviolet absorber compound represented by the above formula (T-5), and Megafuck (registered trademark) R as a surfactant. A solution was obtained by dissolving 0.003 g of -40 (manufactured by DIC Co., Ltd.) in 7.4 g of propylene glycol monomethyl ether acetate and 14.3 g of cyclohexanone. Then, the obtained solution was filtered using a polyethylene microfilter having a pore size of 0.10 μm to prepare a thermosetting resin composition.

<Example 12>
20.0 g of the copolymer solution obtained in Synthesis Example 2, 0.3 g of the compound represented by the above formula (T-4), which is a triazine-based ultraviolet absorber, and Megafuck (registered trademark) R as a surfactant. A solution was obtained by dissolving 0.003 g of -40 (manufactured by DIC Co., Ltd.) in 7.4 g of propylene glycol monomethyl ether acetate and 14.3 g of cyclohexanone. Then, the obtained solution was filtered using a polyethylene microfilter having a pore size of 0.10 μm to prepare a thermosetting resin composition.

<Comparative example 1>
20.0 g of the copolymer solution obtained in Synthesis Example 2 and 0.003 g of Megafvck® R-40 (manufactured by DIC Co., Ltd.) as a surfactant, 6.4 g of propylene glycol monomethyl ether acetate and A solution was obtained by dissolving in 13.6 g of cyclohexanone. Then, the obtained solution was filtered using a polyethylene microfilter having a pore size of 0.10 μm to prepare a thermosetting resin composition. The thermosetting resin composition prepared in this comparative example does not contain an ultraviolet absorber.

<Comparative example 2>
20.0 g of the copolymer solution obtained in Synthesis Example 2, 0.3 g of a benzotriazole-based ultraviolet absorber compound represented by the following formula (BT-1), and Megafuck as a surfactant [registered trademark]. A solution was obtained by dissolving 0.003 g of R-40 (manufactured by DIC Co., Ltd.) in 7.4 g of propylene glycol monomethyl ether acetate and 14.3 g of cyclohexanone. Then, the obtained solution was filtered using a polyethylene microfilter having a pore size of 0.10 μm to prepare a thermosetting resin composition.

<Comparative example 3>
20.0 g of the copolymer solution obtained in Synthesis Example 2, 0.3 g of a benzotriazole-based ultraviolet absorber compound represented by the following formula (BT-2), and Megafuck as a surfactant [registered trademark]. A solution was obtained by dissolving 0.003 g of R-40 (manufactured by DIC Co., Ltd.) in 7.4 g of propylene glycol monomethyl ether acetate and 14.3 g of cyclohexanone. Then, the obtained solution was filtered using a polyethylene microfilter having a pore size of 0.10 μm to prepare a thermosetting resin composition.

<Comparative example 4>
20.0 g of the copolymer solution obtained in Synthesis Example 2, 0.3 g of a benzotriazole-based ultraviolet absorber compound represented by the following formula (BT-3), and Megafuck as a surfactant [registered trademark]. A solution was obtained by dissolving 0.003 g of R-40 (manufactured by DIC Co., Ltd.) in 7.4 g of propylene glycol monomethyl ether acetate and 14.3 g of cyclohexanone. Then, the obtained solution was filtered using a polyethylene microfilter having a pore size of 0.10 μm to prepare a thermosetting resin composition.

<Comparative example 5>
20.0 g of the copolymer solution obtained in Synthesis Example 2, 0.3 g of a benzotriazole-based ultraviolet absorber compound represented by the following formula (BT-4), and Megafuck as a surfactant [registered trademark]. A solution was obtained by dissolving 0.003 g of R-40 (manufactured by DIC Co., Ltd.) in 7.4 g of propylene glycol monomethyl ether acetate and 14.3 g of cyclohexanone. Then, the obtained solution was filtered using a polyethylene microfilter having a pore size of 0.10 μm to prepare a thermosetting resin composition.

<Comparative Example 6>
20.0 g of the copolymer solution obtained in Synthesis Example 2, 0.3 g of a compound represented by the following formula (BP-1) which is a benzophenone-based ultraviolet absorber, and Megafuck [registered trademark] R as a surfactant. A solution was obtained by dissolving 0.003 g of -40 (manufactured by DIC Co., Ltd.) in 7.4 g of propylene glycol monomethyl ether acetate and 14.3 g of cyclohexanone. Then, the obtained solution was filtered using a polyethylene microfilter having a pore size of 0.10 μm to prepare a thermosetting resin composition.

<Comparative Example 7>
20.0 g of the copolymer solution obtained in Synthesis Example 2, 0.3 g of a compound represented by the following formula (BP-2), which is a benzophenone-based ultraviolet absorber, and Megafuck [registered trademark] R as a surfactant. A solution was obtained by dissolving 0.003 g of -40 (manufactured by DIC Co., Ltd.) in 7.4 g of propylene glycol monomethyl ether acetate and 14.3 g of cyclohexanone. Then, the obtained solution was filtered using a polyethylene microfilter having a pore size of 0.10 μm to prepare a thermosetting resin composition.

<Comparative Example 8>
20.0 g of the copolymer solution obtained in Synthesis Example 2, 0.3 g of a compound represented by the following formula (BP-3), which is a benzophenone-based ultraviolet absorber, and Megafuck [registered trademark] R as a surfactant. A solution was obtained by dissolving 0.003 g of -40 (manufactured by DIC Co., Ltd.) in 7.4 g of propylene glycol monomethyl ether acetate and 14.3 g of cyclohexanone. Then, the obtained solution was filtered using a polyethylene microfilter having a pore size of 0.10 μm to prepare a thermosetting resin composition.

<Comparative Example 9>
20.0 g of the copolymer solution obtained in Synthesis Example 2, 0.3 g of a compound represented by the following formula (BP-4), which is a benzophenone-based ultraviolet absorber, and Megafuck [registered trademark] R as a surfactant. A solution was obtained by dissolving 0.003 g of -40 (manufactured by DIC Co., Ltd.) in 7.4 g of propylene glycol monomethyl ether acetate and 14.3 g of cyclohexanone. Then, the obtained solution was filtered using a polyethylene microfilter having a pore size of 0.10 μm to prepare a thermosetting resin composition.

[Solvent resistance test]
The thermosetting resin compositions prepared in Examples 1 to 12 and Comparative Examples 1 to 9 were each applied on a silicon wafer using a spin coater, and placed on a hot plate at 100 ° C. for 1 minute. Further, it was baked at 220 ° C. for 5 minutes to form a cured film having a film thickness of 1 μm. Propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, ethyl lactate, cyclohexanone, 2-propanol and tetramethylammonium hydroxide (hereinafter abbreviated as TMAH) aqueous solution having a concentration of 2.38% by mass are applied to these cured films. After immersing in each of them under a temperature condition of 23 ° C. for 5 minutes, they were baked at 100 ° C. for 1 minute and dried. The film thickness of the cured film before immersion and after drying was measured, and the change in film thickness was calculated. Even one of the solvents used for the immersion is "x" when the film thickness after drying increases or decreases by 5% or more with respect to the film thickness before the immersion, and all the solvents used for the immersion are the films before the immersion. When the increase / decrease in the film thickness after drying was less than 5% with respect to the thickness, the solvent resistance was evaluated as “◯”. The evaluation results are shown in Table 1.

[Refractive index measurement]
The thermosetting resin compositions prepared in Examples 1 to 12 and Comparative Examples 1 to 9 were each applied on a silicon wafer using a spin coater, and placed on a hot plate at 100 ° C. for 1 minute. Further, it was baked at 220 ° C. for 5 minutes to form a cured film having a film thickness of 1 μm. The refractive index of these cured films at a wavelength of 550 nm was measured using a spectroscopic ellipsometer M-2000 (JA Woolam Japan Co., Ltd.). The evaluation results are shown in Table 1.

[Heat resistance test]
The thermosetting resin compositions prepared in Examples 1 to 12 and Comparative Examples 1 to 9 were each applied on a quartz substrate using a spin coater, and placed on a hot plate at 100 ° C. for 1 minute. Further, it was baked at 220 ° C. for 5 minutes to form a cured film having a film thickness of 1 μm. The transmittance of these cured films was measured in the wavelength range of 400 nm to 800 nm using an ultraviolet visible spectrophotometer UV-2600 (manufactured by Shimadzu Corporation). Further, after baking these cured films at 260 ° C. for 5 minutes, the transmittance was measured again in the wavelength range of 400 nm to 800 nm. After baking at 220 ° C. for 5 minutes and after baking at 260 ° C. for 5 minutes, the minimum transmittance measured in the wavelength range of 400 nm to 800 nm was "○", less than 90% when it was 90% or more. The heat resistance was evaluated as "x" when there was a case. The evaluation results are shown in Table 1.

[Light resistance test]
The thermosetting resin compositions prepared in Examples 1 to 12 and Comparative Examples 1 to 9 were each applied on a quartz substrate using a spin coater, and placed on a hot plate at 100 ° C. for 1 minute. Further, it was baked at 220 ° C. for 5 minutes to form a cured film having a film thickness of 1 μm. The transmittance of these cured films was measured in the wavelength range of 400 nm to 800 nm using an ultraviolet visible spectrophotometer UV-2600 (manufactured by Shimadzu Corporation). Further, after conducting a light resistance test on these cured films under the following conditions, the transmittance was measured again in the wavelength range of 400 nm to 800 nm. Before the light resistance test and after the light resistance test, "○" is when the minimum transmittance measured in the wavelength range of 400 nm to 800 nm is 90% or more, and "x" is when it is less than 90%. The light resistance was evaluated as. The evaluation results are shown in Table 1.

[Light resistance test conditions]
Equipment: Xenon accelerated weathering tester Q-Sun Xe-1-B (manufactured by Q-Lab Corporation)
Light source: Xenon arc lamp Optical filter: Window-B / SL
Illuminance: 60 W / m ² (wavelength 300 nm to 400 nm)
Black panel temperature: 63 ° C
Test time: 20 hours

[Step flatness]
The thermosetting resin compositions prepared in Examples 1 to 12 were each applied using a spin coater on a stepped substrate (see FIG. 1) having a height of 0.3 μm, a line width of 10 μm, and a space between lines of 10 μm. , Bake at 100 ° C. for 1 minute and further at 220 ° C. for 5 minutes on a hot plate to form a film having a film thickness of 1 μm. From the values of h1 (step of the stepped substrate) and h2 (step of the cured film, that is, the height difference between the height of the cured film on the line and the height of the cured film on the space) shown in the stepped substrate 1 of FIG. : (1- (h2 / h1)) × 100 ”was used to determine the flattening rate. The step flatness was evaluated as "○" when the flattening rate was 80% or more, "Δ" when it was 50% or more and less than 80%, and "×" when it was less than 50%. .. The evaluation results are shown in Table 1.

[Measurement of dry etching rate]
The thermosetting resin compositions prepared in Examples 1 to 12 were each applied on a silicon wafer using a spin coater, and baked on a hot plate at 100 ° C. for 1 minute and then at 220 ° C. for 5 minutes. A cured film having a film thickness of 1 μm was formed. These cured films were dry-etched using a dry etching apparatus RIE-10NR (manufactured by SAMCO Co., Ltd.) (etching gas: CF ₄ ), and the dry etching rate was measured. Similarly, a resist solution (THMR-iP1800 (manufactured by Tokyo Ohka Kogyo Co., Ltd.)) is applied onto a silicon wafer using a spin coater, and is placed on a hot plate at 90 ° C. for 1.5 minutes and at 110 ° C. for 1.5 minutes. It was baked for 1 minute at 180 ° C. for 1 minute to form a resist film having a thickness of 1 μm, and the dry etching rate was measured. Then, the heat-curable resin composition prepared in Examples 1 to 12 with respect to the resist film. The dry etching rate ratio of the cured film obtained from the product was determined. The evaluation results are shown in Table 1.

From the results in Table 1, the cured film formed from the thermosetting resin composition of the present invention has high solvent resistance, high refractive index, and high transparency, and after heating at 260 ° C. and after a light resistance test. All of them had a minimum transmittance of 90% or more in the wavelength range of 400 nm to 800 nm, and had high heat resistance and high light resistance. Further, all of the cured films formed from the thermosetting resin composition of the present invention had an excellent step flattening property with a flattening rate of 80% or more. Further, in the etch back method, when the lens pattern shape is faithfully transferred to the lower resin layer for microlenses, the dry etching rate X of the resist and the dry etching rate Y of the resin layer for microlenses are equivalent (X: Y = 1). : 0.8 to 1.2), but the cured film formed from the thermosetting resin composition of the present invention has satisfied this result.

On the other hand, although the cured film formed from the thermosetting resin compositions prepared in Comparative Examples 1 to 9 has high solvent resistance, high refractive index and high heat resistance, a light resistance test was conducted. The minimum transmittance in the wavelength range of 400 nm to 800 nm was reduced to less than 90%, resulting in poor light resistance.

From the above, the thermosetting resin composition of the present invention includes a protective film, a flattening film, an insulating film, an antireflection film, a refractive index control film, a microlens, an intralayer lens, an optical waveguide, a film substrate, and the like. It is useful as a resin composition for forming an optical member.

1: Step substrate 2: Hardened film 3: Line width 4: Space between lines h1: Step of stepped substrate h2: Step of cured film

Claims (9)

A self-crosslinking copolymer having a structural unit represented by the following formula (1), a structural unit represented by the following formula (2), and a structural unit represented by the following formula (3), a triazine-based ultraviolet absorber, And an organic solvent, the triazine-based ultraviolet absorber is a thermosetting resin composition contained in a proportion of 3% by mass to 20% by mass with respect to the content of the self-crosslinking copolymer .
The compounds forming the structural unit represented by the formula (1) are 1-vinylnaphthalene, 2-vinylnaphthalene, 6-methyl-2-vinylnaphthalene, 5,8-dimethyl-2-vinylnaphthalene, and 6-methoxy. -2-Vinylnaphthalene, 5,8-dimethoxy-2-vinylnaphthalene, 6-hydroxy-2-vinylnaphthalene, 5,8-dihydroxy-2-vinylnaphthalene, 6-bromo-2-vinylnaphthalene, 5,8- Selected from the group consisting of dibromo-2-vinylnaphthalene, 1-vinylanthracene, 2-vinylanthracene, 9-vinylanthracene, and N-vinylcarbazole.
The compounds forming the structural unit represented by the formula (2) are glycidyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate glycidyl ether, 3,4-epoxycyclopentylmethyl (meth) acrylate, 3,4-. Epoxycyclohexylmethyl (meth) acrylate, 5,6-epoxy-2-bicyclo [2.2.1] heptylmethyl (meth) acrylate, and 3,4-epoxytricyclo [5.2.1.0 ^2,6 ] A thermosetting resin composition selected from the group consisting of decane-8-yl (meth) acrylate.

[In formulas (1) to (3), Ar represents a fused ring hydrocarbon group, R ¹ and R ² each independently represent a hydrogen atom or a methyl group, and R ³ represents a single bond or an alkylene group. , A ¹ represents a group having an oxylan ring, R ⁴ represents an alkyl group, and A ² represents an alkoxy group. ] The thermosetting resin composition according to claim 1, wherein the fused cyclic hydrocarbon group is a naphthyl group. The thermosetting resin composition according to claim 1 or 2, wherein the group having an oxylan ring is an epoxy group. The thermosetting resin composition according to any one of claims 1 to 3, wherein the self-crosslinkable copolymer contains at least 70 mol% of the structural unit represented by the formula (1). The thermosetting resin composition according to any one of claims 1 to 4, wherein the self-crosslinkable copolymer has a weight average molecular weight of 6,000 to 25,000. The triazine-based ultraviolet absorber is a compound containing three phenyl groups which may have a substituent and which are bonded to a triazine ring and a carbon atom of the triazine ring, and at least one of the three phenyl groups. Is the heat-curable resin composition according to any one of claims 1 to 5, which is a group represented by the following formula (4).

(Wherein, * represents a bond to the carbon atom of the triazine ring, A ³ and A ⁴ each independently represent a hydrogen atom or an organic group.) The thermosetting resin composition according to any one of claims 1 to 6, further comprising a surfactant. The thermosetting resin composition according to any one of claims 1 to 7, which is used for a flattening film. The thermosetting resin composition according to any one of claims 1 to 7, which is for a microlens.

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