JP2012042829A - Resin composition for optical waveguide formation and resin film for optical waveguide formation using this, and optical waveguide using them - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition for optical waveguide and a resin film for optical waveguide formation, and an optical waveguide using them which can form an optical waveguide excellent in transparency, heat resistance, environment reliability and toughness with high productivity and workability.SOLUTION: A resin composition for optical waveguide formation, and a resin film for optical waveguide formation using the resin composition for optical waveguide formation, and an optical waveguide using them include (A) a polymer having a carboxyl group, (B) urethane (meth)acrylate, (C) a chemical compound having two or more epoxy groups in a molecule and (D) a radical polymerization initiator.

Description

  The present invention relates to a resin composition for forming an optical waveguide, a resin film for forming an optical waveguide, and an optical waveguide using these, and in particular, a resin composition for forming an optical waveguide having excellent transparency, heat resistance, and toughness, The present invention relates to a resin film for forming an optical waveguide using the resin composition for forming an optical waveguide, and an optical waveguide excellent in transparency, heat resistance, environmental reliability and toughness using the same.

In high-speed and high-density signal transmission between electronic devices and between wiring boards, signal transmission interference and attenuation become barriers in conventional transmission using electric wiring, and the limits of high-speed and high-density are beginning to appear. In order to overcome this, development of a technology for connecting electronic elements and wiring boards with light, so-called optical interconnection technology, has been underway. As an optical transmission line, a polymer optical waveguide has attracted attention because of its ease of processing, low cost, high degree of freedom of wiring, and high density.
As a form of the polymer optical waveguide, a rigid optical waveguide manufactured on a hard support substrate such as a glass epoxy resin that is assumed to be applied to an opto-electric hybrid substrate, or a flexible optical device that does not have a rigid support substrate that assumes connection between boards Waveguides are considered suitable.
Furthermore, by using an opto-electric composite flexible wiring board in which a flexible wiring board and an optical waveguide are integrally combined, the degree of mounting freedom can be further improved.

Polymer optical waveguides are required to have heat resistance and environmental reliability as well as transparency (low light propagation loss) from the viewpoint of the usage environment of equipment to be applied and component mounting. In addition, the demand for toughness is increasing from the viewpoint of the strength and handleability of the optical waveguide. Furthermore, regarding an optical waveguide manufacturing process, a method capable of easily forming a core pattern is required, and one of the methods is a pattern forming method by exposure and development widely used in a printed wiring board manufacturing process. be able to. As such a material, an optical waveguide material containing a (meth) acrylic polymer (for example, see Patent Documents 1 to 4) is known.
Patent Documents 1 and 2 disclose optical waveguide materials that can form a core pattern by exposure and development, have transparency at a wavelength of 850 nm, and have good light propagation loss after a high-temperature and high-humidity test. There is no specific description about the evaluation of heat resistance such as light propagation loss after the solder reflow test of the optical waveguide material, and it is not clear.
Patent Document 3 discloses an optical waveguide material that exhibits excellent optical transmission loss and good heat resistance, but the optical waveguide material is brittle and does not have sufficient toughness.
Patent Document 4 discloses an optical waveguide material that is transparent at a wavelength of 850 nm and has excellent toughness. However, the evaluation of heat resistance such as light propagation loss after a solder reflow test of the optical waveguide material is possible. However, there is no specific description about the evaluation of environmental reliability such as light propagation loss after the high temperature and high humidity leaving test or the temperature cycle test, and it is not clear.

JP 2006-146162 A JP 2008-33239 A JP 2006-71880 A JP 2007-1222023 A

In view of the above problems, the present invention provides an optical waveguide resin composition and an optical waveguide forming resin film capable of forming an optical waveguide excellent in transparency, heat resistance, environmental reliability, and toughness with good productivity and workability. The purpose is to provide.
Moreover, according to this invention, the resin composition for optical waveguides and the resin film for optical waveguide formation excellent in transparency, heat resistance, and toughness are provided.

  As a result of intensive studies, the present inventors have found that an optical waveguide includes a polymer having a carboxyl group, a urethane (meth) acrylate, a compound having two or more epoxy groups in the molecule, and a radical polymerization initiator. The present inventors have found that the above problems can be solved by using a resin composition, and have reached the present invention.

That is, the present invention provides the following [1] to [4].
[1] An optical waveguide comprising (A) a polymer having a carboxyl group, (B) a urethane (meth) acrylate, (C) a compound having two or more epoxy groups in the molecule, and (D) a radical polymerization initiator. Resin composition for forming.
[2] A resin film for forming an optical waveguide using the resin composition for forming an optical waveguide according to [1].
[3] An optical waveguide having a core part and / or a clad layer using the resin composition for forming an optical waveguide according to [1].
[4] An optical waveguide having a core part and / or a cladding layer using the optical waveguide forming resin film according to [2].

  According to the present invention, a resin composition for forming an optical waveguide and an optical waveguide forming that are excellent in transparency, heat resistance, and toughness, can form a highly accurate thick film, and can produce an optical waveguide with high productivity and workability. Resin film is provided. Therefore, according to the present invention, an optical waveguide excellent in transparency, heat resistance, environmental reliability, and toughness can be provided.

It is sectional drawing explaining the form of the optical waveguide of this invention. The temperature profile in the reflow furnace in the reflow test implemented by this invention is shown.

[Resin composition for optical waveguide formation]
The resin composition for forming an optical waveguide of the present invention includes (A) a polymer having a carboxyl group ((A) component), (B) urethane (meth) acrylate ((B) component), and (C) two in the molecule. The compound ((C) component) which has the above epoxy groups, and (D) radical polymerization initiator ((D) component) are included. Further, (E) (meth) acrylate having no urethane bond ((E) component) and / or (F) curing accelerator ((F) component) is preferably included.
First, each component contained in the resin composition for forming an optical waveguide of the present invention will be described.

<(A) Polymer having carboxyl group>
The resin composition for forming an optical waveguide of the present invention includes (A) a polymer having a carboxyl group. By blending the component (A), the carboxyl group of the component (A) reacts with the epoxy group of the component (C) by heating to form a new crosslinked structure, so that the heat resistance and environmental reliability of the optical waveguide are formed. Can be improved.
When the amount of the component (A) does not include the component (E), the amount of the component (A) to the component (C) is preferably 10 to 85% by mass, more preferably 15 to 80% by mass, and further, Preferably it is 20-75 mass%. When it is 10% by mass or more, the carboxyl group of the component (A) and the epoxy group of the component (C) react to form a sufficient crosslinked structure, so that the heat resistance becomes good, and when it is 85% by mass or less, It is preferable because it has good toughness and does not become brittle.
Moreover, the compounding quantity of (A) component in the case of containing (E) component, Preferably it is 10-85 mass with respect to the total amount of (A)-(C) and (E) component from a viewpoint similar to the above. %, More preferably, it is 15-80 mass%, More preferably, it is 20-75 mass%.

There is no restriction | limiting in particular as (A) component, For example, the polymer represented by following (I)-(VIII) is mentioned.
(I) A polymer obtained by copolymerizing a compound having a carboxyl group and an ethylenically unsaturated group in the molecule with a compound having another ethylenically unsaturated group.
(II) An ethylenically unsaturated group is added to the side chain of a polymer obtained by copolymerizing a compound having a carboxyl group and an ethylenically unsaturated group in the molecule with a compound having another ethylenically unsaturated group. Polymer obtained by partial introduction.
(III) A polymer obtained by copolymerizing a compound having an epoxy group and an ethylenically unsaturated group in the molecule with another compound having an ethylenically unsaturated group is converted into a carboxyl group and an ethylenically unsaturated group in the molecule. A polymer obtained by reacting a compound having a saturated group and reacting the resulting hydroxyl group with a polybasic acid anhydride.
(IV) A compound having a hydroxyl group and an ethylenically unsaturated group in a molecule obtained by copolymerizing an acid anhydride having an ethylenically unsaturated group and another compound having an ethylenically unsaturated group Polymer obtained by reacting
(V) A polymer obtained by reacting a polybasic acid anhydride with a hydroxyl group of a polymer obtained by copolymerizing a bifunctional epoxy resin and a bifunctional phenol compound.
(VI) A polymer obtained by reacting a polybasic acid anhydride with a hydroxyl group of a polymer obtained by copolymerizing a bifunctional epoxy resin and a bifunctional carboxylic acid compound.
(VII) A polymer obtained by reacting a polybasic acid anhydride with a hydroxyl group of a polymer obtained by copolymerizing a bifunctional oxetane compound and a bifunctional phenol compound.
(VIII) A polymer obtained by reacting a polybasic acid anhydride with a hydroxyl group of a polymer obtained by copolymerizing a bifunctional oxetane compound and a bifunctional carboxylic acid compound.

  Among these, from the viewpoint of transparency, the polymers of (I) to (IV) are preferable, and (meth) acrylic polymers having structural units represented by the following general formulas (1) and (2) are more preferable.

In formula (1), R ¹ represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms, R ² represents a hydrogen atom or a methyl group, and X ¹ is a single bond or 2 having 1 to 20 carbon atoms. A valent organic group.
The monovalent organic group having 1 to 20 carbon atoms represented by R ¹ is not particularly limited, for example, an alkyl group means a cycloalkyl group, an aryl group, an aralkyl group, a carbonyl group (-CO-R. However , R is a hydrocarbon group), an ester group (—CO—O—R or —O—CO—R, where R is a hydrocarbon group), an amide group (—CO—NR ₂ or -NR-CO-R, where R is a hydrogen atom or a hydrocarbon group. Among these, an alkyl group, a cycloalkyl group, an aryl group, and an aralkyl group are preferable from the viewpoint of transparency and heat resistance. These monovalent organic groups further include a hydroxyl group, a halogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, a carbonyl group, a formyl group, an ester group, an amide group, an alkoxy group, an aryloxy group, and an alkylthio group. , Arylthio group, amino group, silyl group, silyloxy group and the like.

Examples of the divalent organic group having 1 to 20 carbon atoms X ¹ represents, not particularly limited, for example, an alkylene group, a cycloalkylene group, a phenylene group, a biphenylene group, a polyether group, a polysiloxane group, a carbonyl group, an ester Group, amide group, urethane group and the like. Among these, an alkylene group, a cycloalkylene group, a phenylene group, and a biphenylene group are preferable from the viewpoint of transparency and heat resistance. These divalent organic groups further include a halogen atom, alkyl group, cycloalkyl group, aryl group, aralkyl group, carbonyl group, formyl group, ester group, amide group, alkoxy group, aryloxy group, alkylthio group, arylthio group. It may be substituted with a group, a silyl group, a silyloxy group or the like.

In formula (2), R ³ represents a hydrogen atom or a methyl group, and R ⁴ represents a monovalent organic group having 1 to 20 carbon atoms. As the monovalent organic group having 1 to 20 carbon atoms include the same R ¹ in the formula (1).

  Said (meth) acrylic polymer means the polymer obtained by copolymerizing the monomer which has (meth) acryloyl groups, such as acrylic acid, acrylic ester, methacrylic acid, methacrylic ester, and these derivatives. Here, the (meth) acryloyl group means an acryloyl group and / or a methacryloyl group. Furthermore, within the range not inhibiting the effects of the present invention, the (meth) acrylic polymer comprises a monomer having a (meth) acrylyl group and a monomer other than the above having an ethylenically unsaturated group other than the (meth) acryloyl group. It may be a copolymer. Further, it may be a mixture of a plurality of (meth) acrylic polymers.

  In the (meth) acrylic polymer, the compound that is a raw material for the structural unit represented by the general formula (1) is not particularly limited. Acid, citraconic acid, mesaconic acid, itaconic acid, mono (2- (meth) acryloyloxyethyl) succinate, mono (2- (meth) acryloyloxyethyl) phthalate, mono (2- (meth) acryloyloxyethyl) isophthalate , Mono (2- (meth) acryloyloxyethyl) terephthalate, mono (2- (meth) acryloyloxyethyl) tetrahydrophthalate, mono (2- (meth) acryloyloxyethyl) hexahydrophthalate, mono (2- (meth) (Acryloyloxyethyl) hexahydroisophthalate, mono ( - (meth) acryloyloxyethyl) hexahydroterephthalate, .omega.-carboxy - polycaprolactone mono (meth) acrylate, 3-vinylbenzoic acid, 4-vinylbenzoic acid.

Among these, from the viewpoint of transparency, heat resistance, and solubility in an alkali developer, (meth) acrylic acid, crotonic acid, maleic acid, fumaric acid, mono (2- (meth) acryloyloxyethyl) succinate, Mono (2- (meth) acryloyloxyethyl) tetrahydrophthalate, mono (2- (meth) acryloyloxyethyl) hexahydrophthalate, mono (2- (meth) acryloyloxyethyl) hexahydroisophthalate, mono (2- ( (Meth) acryloyloxyethyl) hexahydroterephthalate is preferred.
In addition, a compound having an ethylenically unsaturated group and an acid anhydride group such as maleic anhydride, citraconic anhydride, and itaconic anhydride is used as a raw material. However, it may be converted into a structural unit represented by the general formula (1).
These compounds can be used individually or in combination of 2 or more types.

  The content of the structural unit represented by the general formula (1) is preferably 5 to 60 mol%, more preferably 10 to 50 mol%, still more preferably 15 to 40 mol, based on the entire (meth) acrylic polymer. %. When it is 5 mol% or more, the carboxyl group of component (A) and the epoxy group of component (C) react to form a sufficient cross-linked structure, resulting in good heat resistance, and when it is 60 mol% or less, toughness Is preferable because it is favorable and does not become brittle.

  In the (meth) acrylic polymer, the compound that is a raw material of the structural unit represented by the general formula (2) is not particularly limited. For example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate , Isopropyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, butoxyethyl (meth) acrylate, pentyl (meth) acrylate, hexyl ( (Meth) acrylate, 2-ethylhexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, undecyl (meth) acrylate, lauryl (medium) ) Acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, stearyl (meth) acrylate, behenyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2- Hydroxypropyl (meth) acrylate, 3-chloro-2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, ethoxypolyethylene glycol (meth) acrylate, methoxypolypropylene glycol (meta ) Aliphatic (meth) acrylates such as acrylate and ethoxypolypropylene glycol (meth) acrylate; cyclopentyl (meth) acrylate Cyclohexane (meth) acrylate, cyclopentyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, isobornyl (meth) acrylate, and other alicyclic (meth) acrylates; phenyl (meth) Acrylate, benzyl (meth) acrylate, o-biphenyl (meth) acrylate, 1-naphthyl (meth) acrylate, 2-naphthyl (meth) acrylate, phenoxyethyl (meth) acrylate, p-cumylphenoxyethyl (meth) acrylate, o-phenylphenoxyethyl (meth) acrylate, 1-naphthoxyethyl (meth) acrylate, 2-naphthoxyethyl (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, noni Ruphenoxypolyethylene glycol (meth) acrylate, phenoxypolypropylene glycol (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, 2-hydroxy-3- (o-phenylphenoxy) propyl (meth) acrylate, 2- Aromatic (meth) acrylates such as hydroxy-3- (1-naphthoxy) propyl (meth) acrylate and 2-hydroxy-3- (2-naphthoxy) propyl (meth) acrylate; 2-tetrahydrofurfuryl (meth) acrylate, Examples thereof include heterocyclic (meth) acrylates such as N- (meth) acryloyloxyethyl hexahydrophthalimide and 2- (meth) acryloyloxyethyl-N-carbazole.

Among these, from the viewpoint of transparency and heat resistance, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate , 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, aliphatic (meth) acrylate such as 2-hydroxybutyl (meth) acrylate; the alicyclic (meth) acrylate; the aromatic (meta ) Acrylates; the above heterocyclic (meth) acrylates are preferred.
These compounds can be used individually or in combination of 2 or more types.

  The content of the structural unit represented by the general formula (2) is preferably 40 to 95 mol%, more preferably 50 to 90 mol%, still more preferably 60 to 85 mol, based on the entire (meth) acrylic polymer. %. When it is 40 mol% or more, the toughness is good and does not become brittle, and when it is 95 mol% or less, the carboxyl group of the component (A) and the epoxy group of the component (C) react with each other to provide a sufficient crosslinked structure. Is preferable because heat resistance is improved.

  The (meth) acrylic polymer is a maleimide skeleton represented by the following general formula (3) in addition to the structural units represented by the above formulas (1) and (2) as necessary from the viewpoint of heat resistance. It may have a derived structural unit.

In formula (3), R ⁵ represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms. As the monovalent organic group having 1 to 20 carbon atoms include the same R ¹ in the formula (1).

In the (meth) acrylic polymer, the compound that is a raw material of the structural unit derived from the maleimide skeleton represented by the general formula (3) is not particularly limited. For example, N-methylmaleimide, N-ethylmaleimide, N-propyl Maleimide, N-isopropylmaleimide, N-2,2-dimethylpropylmaleimide, N-butylmaleimide, N-isobutylmaleimide, N-sec-butylmaleimide, N-tert-butylmaleimide, N-2-methyl-2-butyl Maleimide, N-pentylmaleimide, N-2-pentylmaleimide, N-3-pentylmaleimide, N-hexylmaleimide, N-2-hexylmaleimide, N-3-hexylmaleimide, N-2-ethylhexylmaleimide, N-heptyl Maleimide, N-octylmaleimide, N-no Alkylmaleimides such as nilmaleimide, N-decylmaleimide, N-hydroxymethylmaleimide, N-2-hydroxyethylmaleimide, N-2-hydroxypropylmaleimide; N-cyclopentylmaleimide, N-cyclohexylmaleimide, N-cycloheptylmaleimide, N-cyclooctylmaleimide, N-2-methylcyclohexylmaleimide, N-2-ethylcyclohexylmaleimide, N-2-chlorocyclohexylmaleimide and other cycloalkylmaleimides; N-phenylmaleimide, N-2-methylphenylmaleimide, N- Examples thereof include arylmaleimides such as 2-ethylphenylmaleimide, N-2-chlorophenylmaleimide, and N-benzylmaleimide.
Among these, from the viewpoints of transparency and heat resistance, N-methylmaleimide, N-ethylmaleimide, N-propylmaleimide, N-isopropylmaleimide, N-butylmaleimide, N-isobutylmaleimide, N-sec-butylmaleimide, Alkyl maleimides such as N-tert-butylmaleimide; cycloalkyl maleimides; aryl maleimides are preferably used, and N-isopropylmaleimide, N-cyclopentylmaleimide, N-cyclohexylmaleimide, N-2-methylcyclohexylmaleimide, N- Phenylmaleimide and N-benzylmaleimide are preferred.
These compounds can be used individually or in combination of 2 or more types.

  When it has a structural unit derived from a maleimide skeleton represented by the general formula (3), the content thereof is preferably 1 to 60 mol%, more preferably 3 to 50 mol%, based on the (meth) acrylic polymer. More preferably, it is 5-40 mol%. When it is 1 mol% or more, heat resistance derived from the maleimide skeleton can be obtained, and when it is 60 mol% or less, transparency is sufficiently secured, and the toughness is good and does not become brittle.

The (meth) acrylic polymer may have structural units other than the structural units represented by the general formulas (1) to (3) as necessary.
There is no restriction | limiting in particular as a compound which has an ethylenically unsaturated group used as the raw material of such a structural unit, For example, styrene, alpha-methylstyrene, beta-methylstyrene, 3-methylstyrene, 4-methylstyrene, alpha , 2-dimethylstyrene, 2,4-dimethylstyrene, 2,5-dimethylstyrene, (meth) acrylonitrile, vinyl cyclohexyl ether, vinyl phenyl ether, vinyl benzyl ether, vinyl acetate, N-vinyl pyrrolidone, N-vinyl carbazole, Examples include vinyl pyridine, vinyl chloride, vinylidene chloride and the like.
Among these, from the viewpoint of transparency and heat resistance, styrene, α-methylstyrene, β-methylstyrene, 3-methylstyrene, 4-methylstyrene, α, 2-dimethylstyrene, 2,4-dimethylstyrene, 2 , 5-dimethylstyrene, (meth) acrylonitrile, vinyl acetate and N-vinylcarbazole are preferred.
These compounds can be used individually or in combination of 2 or more types.

  The method for synthesizing the (meth) acrylic polymer is not particularly limited, and examples thereof include a method of copolymerizing while heating using a compound that is a raw material of the above-described structural unit and an appropriate thermal radical polymerization initiator. . At this time, if necessary, an organic solvent and / or water can be used as a reaction solvent, and a chain transfer agent, a dispersant, a surfactant, an emulsifier, and the like may be used in combination.

  The thermal radical polymerization initiator is not particularly limited, and examples thereof include ketone peroxides such as methyl ethyl ketone peroxide, cyclohexanone peroxide, and methylcyclohexanone peroxide; 1,1-bis (t-butylperoxy) cyclohexane, 1,1 -Bis (t-butylperoxy) -2-methylcyclohexane, 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, 1,1-bis (t-hexylperoxy) cyclohexane Peroxyketals such as 1,1-bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane; hydroperoxides such as p-menthane hydroperoxide; α, α′-bis (t-butyl Peroxy) diisopropylbenzene, dicumyl peroxide, t-butyl Dialkyl peroxides such as cumyl peroxide and di-t-butyl peroxide; diacyl peroxides such as octanoyl peroxide, lauroyl peroxide, stearyl peroxide and benzoyl peroxide; bis (4-t-butylcyclohexyl) peroxy Peroxycarbonates such as dicarbonate, di-2-ethoxyethyl peroxydicarbonate, di-2-ethylhexyl peroxydicarbonate, di-3-methoxybutyl peroxycarbonate; t-butyl peroxypivalate, t-hexyl Peroxypivalate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, 2,5-dimethyl-2,5-bis (2-ethylhexanoylperoxy) hexane, t- Hexylperoxy-2 Ethylhexanoate, t-butylperoxy-2-ethylhexanoate, t-butylperoxyisobutyrate, t-hexylperoxyisopropylmonocarbonate, t-butylperoxy-3,5,5-trimethylhexa Noate, t-butyl peroxylaurate, t-butyl peroxyisopropyl monocarbonate, t-butyl peroxy-2-ethylhexyl monocarbonate, t-butyl peroxybenzoate, t-hexyl peroxybenzoate, 2,5- Peroxyesters such as dimethyl-2,5-bis (benzoylperoxy) hexane, t-butylperoxyacetate; 2,2′-azobisisobutyronitrile, 2,2′-azobis (2,4-dimethyl) Valeronitrile), 2,2′-azobis (4- Butoxy-2'-dimethylvaleronitrile) azo compounds, and the like.

The organic solvent used as the reaction solvent is not particularly limited as long as it can dissolve the (meth) acrylic polymer. For example, aromatic hydrocarbons such as toluene, xylene, mesitylene, cumene, and p-cymene; diethyl Chain ethers such as ether, tert-butyl methyl ether, cyclopentyl methyl ether and dibutyl ether; Cyclic ethers such as tetrahydrofuran and 1,4-dioxane; Alcohols such as methanol, ethanol, isopropanol, butanol, ethylene glycol and propylene glycol; Acetone , Methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone, etc .; methyl acetate, ethyl acetate, butyl acetate, methyl lactate, ethyl lactate, γ-butyrolacto Esters such as ethylene carbonate and propylene carbonate; ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, Ethylene glycol Bifunctional alcohol alkyl ether acetates such as rumonomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate; Examples include amides such as N, N-dimethylformamide, N, N-dimethylacetamide, and N-methylpyrrolidone.
These compounds can be used individually or in combination of 2 or more types.

The weight average molecular weight of the component (A) is preferably 1.0 × 10 ^{3 to} 1.0 × 10 ⁶ , more preferably 3.0 × 10 ^{3 to} 5.0 × 10 ⁵ , still more preferably 5.0 ×. 10 ^{3 to} 3.0 × 10 ⁵ . If it is 1.0 × 10 ³ or more, the toughness is good and does not become brittle because the molecular weight is large, and if it is 1.0 × 10 ⁶ or less, solubility in a developer, The compatibility with the component (C) is favorable, which is preferable.
The weight average molecular weight in the present invention is a value measured by gel permeation chromatography (GPC) and converted to standard polystyrene.

(A) The acid value of a component is prescribed | regulated by the value which can be developed with the below-mentioned alkali developing solution.
When an aqueous alkaline developer composed of an aqueous alkaline solution is used as the alkaline developer, the acid value of the component (A) is preferably 30 to 250 mgKOH / g, more preferably 35 to 200 mgKOH / g, still more preferably 40 to 170 mgKOH / g. It is. When it is 30 mgKOH / g or more, the solubility in an alkali developer is good, and when it is 250 mgKOH / g or less, the portion that becomes a pattern without being removed by development is not affected by the developer. It is preferable because the liquidity is good.

  When a semi-aqueous alkaline developer composed of an aqueous alkali solution and one or more organic solvents is used as the alkaline developer, the acid value of the component (A) is preferably 20 to 200 mgKOH / g, more preferably 25 to 170 mgKOH / g, more preferably 30 to 150 mg KOH / g. When it is 20 mgKOH / g or more, the solubility in an alkali developer is good, and when it is 200 mgKOH / g or less, the developer resistance is good.

<(B) (Meth) acrylate having urethane bond>
The resin composition for forming an optical waveguide of the present invention contains (B) urethane (meth) acrylate having a urethane bond. (B) Toughness can be improved by mix | blending a component.
When the component (B) does not contain the component (E), the amount is preferably 10 to 85% by mass, more preferably 15 to 80% by mass, and more preferably 15 to 80% by mass, based on the total amount of the components (A) to (C). Preferably it is 20-75 mass%. When it is 10% by mass or more, the toughness is good and does not become brittle, and when it is 85% by mass or less, the carboxyl group of the component (A) and the epoxy group of the component (C) react with each other to provide a sufficient crosslinked structure. Is preferable because heat resistance is improved.
Moreover, the compounding quantity of (A) component in the case of containing (E) component, Preferably it is 5-80 from a viewpoint similar to the above with respect to the total amount of (A)-(C) and (E) component. It is 10 mass%, More preferably, it is 10-75 mass%, More preferably, it is 15-70 mass%.

There is no restriction | limiting in particular as (B) component, For example, the urethane (meth) acrylate represented by following (I)-(IV) is mentioned.
(I) Urethane (meth) acrylate obtained by reacting a bifunctional alcohol compound, a bifunctional isocyanate compound, and a (meth) acrylate having a hydroxyl group.
(II) Urethane (meth) acrylate obtained by reacting a bifunctional alcohol compound, a bifunctional isocyanate compound, and a (meth) acrylate having an isocyanate group.
(III) Urethane (meth) acrylate obtained by reacting a polyfunctional isocyanate compound with (meth) acrylate having a hydroxyl group.
(IV) Urethane (meth) acrylate obtained by reacting a polyfunctional alcohol compound with (meth) acrylate having an isocyanate group.

  There is no restriction | limiting in particular as a bifunctional alcohol compound, ie, a diol compound, For example, a polyether diol compound, a polyester diol compound, a polycarbonate diol compound, a polycaprolactone diol compound etc. are mentioned.

  The polyether diol compound is not particularly limited, and examples thereof include ethylene oxide, propylene oxide, isobutene oxide, butyl glycidyl ether, butene-1-oxide, 3,3-bischloromethyloxetane, tetrahydrofuran, 2-methyltetrahydrofuran, 3- Polyether diol compounds obtained by ring-opening (co) polymerizing at least one selected from cyclic ether compounds such as methyltetrahydrofuran, cyclohexene oxide, styrene oxide, phenyl glycidyl ether, glycidyl benzoate; cyclohexanedimethanol, tri An alicyclic diol compound such as cyclodecane dimethanol, hydrogenated bisphenol A, hydrogenated bisphenol F or the like is selected from at least one selected from the above cyclic ether compounds. Polyether diol compound obtained by ring-opening addition; bifunctional phenol compound such as hydroquinone, resorcinol, catechol, bisphenol A, bisphenol F, bisphenol AF, biphenol, and fluorene bisphenol, at least one selected from the above cyclic ether compounds Examples thereof include polyether diol compounds obtained by ring-opening addition.

  The polyester diol compound is not particularly limited. For example, malonic acid, succinic acid, glutaric acid, adipic acid, sebacic acid, tetrahydrophthalic acid, hexahydrophthalic acid, phthalic acid, isophthalic acid, terephthalic acid, maleic acid, fumaric acid. Bifunctional carboxylic acid compounds such as acid and itaconic acid and ethylene glycol, diethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, butanediol, dibutanediol, polybutanediol, pentanediol, neopentylglycol, 3- Methyl-1,5-pentanediol, hexanediol, heptanediol, octanediol, nonanediol, decanediol, cyclohexanedimethanol, tricyclodecane dimeta Lumpur polyester polyol compounds obtained diol compound copolymerized with such like.

  The polycarbonate diol compound is not particularly limited. Butanediol, pentanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, hexanediol, heptanediol, octanediol, nonanediol, decanediol, cyclohexanedimethanol, tricyclodecanedimethanol, hydrogenated bisphenol A Polycarbonate diol compounds obtained by copolymerizing diol compounds such as hydrogenated bisphenol F And the like.

  The polycaprolactone diol compound is not particularly limited. For example, ε-caprolactone and ethylene glycol, diethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, butanediol, dibutanediol, polybutanediol, pentanediol, It is obtained by copolymerizing diol compounds such as neopentyl glycol, 3-methyl-1,5-pentanediol, hexanediol, heptanediol, octanediol, nonanediol, decanediol, cyclohexanedimethanol, and tricyclodecanedimethanol. Examples include polycaprolactone diol compounds.

Examples of other diol compounds include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, butanediol, dibutanediol, pentanediol, neopentylglycol, 3-methyl-1,5-pentanediol, hexanediol, and heptane. Aliphatic diol compounds such as diol, octanediol, nonanediol, decanediol; cycloaliphatic diol compounds such as cyclohexanedimethanol, tricyclodecanedimethanol, hydrogenated bisphenol A, hydrogenated bisphenol F; polybutadiene-modified diol compounds, water Examples thereof include modified diol compounds such as an additive polybutadiene-modified diol compound and diglycone-modified diol compound.
The above diol compounds can be used alone or in combination of two or more.

  The bifunctional isocyanate compound is not particularly limited, and examples thereof include aliphatic bifunctional isocyanate compounds such as tetramethylene diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, decamethylene diisocyanate, and dodecamethylene diisocyanate. 1,3-bis (isocyanatomethyl) cyclohexane, isophorone diisocyanate, 2,5-bis (isocyanatomethyl) norbornene, bis (4-isocyanatocyclohexyl) methane, 1,2-bis (4-isocyanatocyclohexyl); Fats such as ethane, 2,2-bis (4-isocyanatocyclohexyl) propane, 2,2-bis (4-isocyanatocyclohexyl) hexafluoropropane, bicycloheptane triisocyanate Cyclic bifunctional isocyanate compounds; 2,4′-diphenylmethane diisocyanate, 4,4′-diphenylmethane diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, naphthalene-1,5-diisocyanate, o-xylylene Examples thereof include aromatic bifunctional isocyanate compounds such as range isocyanate and m-xylylene diisocyanate. These compounds can be used individually or in combination of 2 or more types.

  The (meth) acrylate having a hydroxyl group is not particularly limited, and examples thereof include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-chloro-2-hydroxypropyl (meth) acrylate, 2- Hydroxybutyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, 2-hydroxy-3- (o-phenylphenoxy) propyl (meth) acrylate, 2-hydroxy-3- (1-naphthoxy) propyl Monofunctional (meth) acrylates such as (meth) acrylate, 2-hydroxy-3- (2-naphthoxy) propyl (meth) acrylate, ethoxylated products thereof, propoxylated products thereof, ethoxylated propoxylated products thereof, And their caprolactone-modified products Bifunctional (meth) acrylates such as bis (2- (meth) acryloyloxyethyl) (2-hydroxyethyl) isocyanurate, ethoxylated forms thereof, propoxylated forms thereof, ethoxylated propoxylated forms thereof, and These caprolactone modified products: cyclohexanedimethanol type epoxy di (meth) acrylate, tricyclodecane dimethanol type epoxy di (meth) acrylate, hydrogenated bisphenol A type epoxy di (meth) acrylate, hydrogenated bisphenol F type epoxy di (meth) acrylate, Hydroquinone type epoxy di (meth) acrylate, resorcinol type epoxy di (meth) acrylate, catechol type epoxy di (meth) acrylate, bisphenol A type epoxy di (meth) acrylate, bisphenol F type Bifunctional epoxy (meth) acrylates such as poxydi (meth) acrylate, bisphenol AF type epoxy di (meth) acrylate, biphenol type epoxy di (meth) acrylate, fluorene bisphenol type epoxy di (meth) acrylate, and isocyanuric acid monoallyl type epoxy di (meth) acrylate Tri- or higher functional (meth) acrylates such as pentaerythritol tri (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, ethoxylated compounds thereof, propoxylated compounds thereof, and the like Ethoxylated propoxy compounds thereof, and their caprolactone-modified products; phenol novolac type epoxy (meth) acrylate, cresol novolac type epoxy poly ( Data) acrylate, isocyanuric acid-type epoxy tri (meth) trifunctional or more epoxy acrylates such as (meth) acrylate. These compounds can be used individually or in combination of 2 or more types.

Here, the ethoxylated product, propoxylated product, and ethoxylated propoxylated product of (meth) acrylate are alcohol compounds or phenol compounds (for example, monofunctional (meth) acrylate; CH ₂ ═CH (R ⁶ ) as a raw material. -COO-R ⁷ (R ⁶ is a hydrogen atom or a methyl group, R ₇ is a monovalent organic group) in the case of, instead of one) represented by HO-R ^7, the above-mentioned alcohol compound or a phenol compound, respectively An alcohol compound having a structure in which one or more ethylene oxides are added, an alcohol compound having a structure in which one or more propylene oxides are added, or an alcohol compound having a structure in which one or more ethylene oxides and propylene oxide are added are used as raw materials ( (Meth) acrylate (for example, in the case of an ethoxylated product, CH ₂ ═CH (R ⁶ ) —COO— (CH ₂ CH ₂ O) _q -R ⁷ (q is an integer of 1 or more, R ⁶ and R ⁷ are the same as above). The modified caprolactone is a (meth) acrylate obtained by using, as a raw material, an alcohol compound obtained by modifying an alcohol compound as a raw material of (meth) acrylate with ε-caprolactone (for example, monofunctional (meth) acrylate) In the case of a modified caprolactone of the formula (1), CH ₂ = CH (R ⁶ ) —COO — ((CH ₂ ) ₅ COO) _q —R ⁷ (where q, R ⁶ and R ⁷ are the same as above))).

The (meth) acrylate having an isocyanate group is not particularly limited. For example, N- (meth) acryloyl isocyanate, (meth) acryloyloxymethyl isocyanate, 2- (meth) acryloyloxyethyl isocyanate, 2- (meth) acryloyl Examples thereof include oxyethoxyethyl isocyanate and 1,1-bis ((meth) acryloyloxymethyl) ethyl isocyanate.
These compounds can be used individually or in combination of 2 or more types.

There is no restriction | limiting in particular as a polyfunctional isocyanate compound, For example, multimers, such as the said bifunctional isocyanate compound; The uretdione type dimer of the said bifunctional isocyanate compound, an isocyanurate type, a biuret type trimer, etc. are mentioned. The two or three bifunctional isocyanate compounds constituting the multimer may be the same or different.
These compounds can be used individually or in combination of 2 or more types.

There is no restriction | limiting in particular as a polyfunctional alcohol compound, For example, more than trifunctional, such as the said bifunctional alcohol compound; Trimethylol propane, pentaerythritol, ditrimethylol propane, dipentaerythritol, tris (2-hydroxyethyl) isocyanurate, etc. Alcohol compounds, adducts obtained by ring-opening addition of at least one selected from the above cyclic ether compounds to these, caprolactone-modified products thereof; the above cyclic ethers to trifunctional or higher functional phenol compounds such as phenol novolac and cresol novolak Examples include alcohol compounds obtained by ring-opening addition of at least one selected from the compounds, and modified caprolactones thereof.
These compounds can be used individually or in combination of 2 or more types.

  Among these (B) components, urethane (meth) acrylate having at least one selected from the group consisting of an alicyclic structure, an aromatic ring structure, and a heterocyclic structure in the molecule from the viewpoint of transparency and heat resistance. Is preferred.

Moreover, it is preferable that urethane (meth) acrylate which has a carboxyl group is included as (B) component from a heat resistant and soluble viewpoint to an alkali developing solution.
The urethane (meth) acrylate having a carboxyl group is not particularly limited. For example, when synthesizing the urethane (meth) acrylate described above, a compound obtained by using a carboxyl group-containing diol compound and the diol compound in combination, The compound etc. which are obtained using a carboxyl group-containing diol compound instead of the said diol compound are mentioned.
The carboxyl group-containing diol compound is not particularly limited, and examples thereof include 2,2-dimethylolbutanoic acid, 2,2-dimethylolpropionic acid, 2,2-dimethylolbutyric acid, 2,2-dimethylolpentanoic acid, and the like. Can be mentioned. These compounds can be used alone or in combination of two or more.

  The urethane (meth) acrylate having a carboxyl group can have an acid value so that it can be developed with an alkali developer described later. The acid value of the urethane (meth) acrylate having a carboxyl group is preferably 5 to 200 mgKOH / g, more preferably 10 to 170 mgKOH / g, and still more preferably 15 to 150 mgKOH / g. If it is 5 mgKOH / g or more, the solubility in an alkali developer is good, and if it is 200 mgKOH / g or less, the developer resistance is good, which is preferable.

<(C) Compound having two or more epoxy groups in the molecule>
The resin composition for forming an optical waveguide of the present invention includes (C) a compound having two or more epoxy groups in the molecule. By blending the component (C), the epoxy group of the component (C) reacts with the carboxyl group of the component (A) by heating to form a new crosslinked structure. Reliability can be improved.
When the amount of component (C) does not include component (E), it is preferably 1 to 40% by weight, more preferably 3 to 35% by weight, and more preferably 3 to 35% by weight, based on the total amount of components (A) to (C). Preferably it is 5-30 mass%. If it is 1% by mass or more, a sufficient cross-linked structure is formed and heat resistance becomes good, and if it is 40% by mass or less, toughness becomes good and it does not become brittle.
Moreover, the compounding quantity of (C) component in the case of containing (E) component, Preferably it is 1-40 mass with respect to the total amount of (A)-(C) and (E) component from a viewpoint similar to the above. %, More preferably, it is 3-35 mass%, More preferably, it is 5-30 mass%.

Examples of the component (C) include polyfunctional aliphatic alcohol glycidyl ethers such as polyethylene glycol type epoxy resins and polypropylene glycol type epoxy resins; hydrogenated bisphenol A type epoxy resins, hydrogenated bisphenol F type epoxy resins, hydrogenated 2, Polyfunctional alicyclic alcohol glycidyl ether such as 2′-biphenol type epoxy resin, hydrogenated 4,4′-biphenol type epoxy resin, tricyclodecane dimethanol type epoxy resin; bisphenol A type epoxy resin, tetrabromobisphenol A type Epoxy resin, bisphenol F type epoxy resin, bisphenol AF type epoxy resin, bisphenol AD type epoxy resin, fluorene bisphenol type epoxy resin, biphenyl type epoxy resin, naphthalene type epoxy resin, pheno Polyfunctional phenol glycidyl ethers such as lunavolac type epoxy resin, cresol novolac type epoxy resin, phenol aralkyl type epoxy resin, cresol aralkyl type epoxy resin, dicyclopentadiene-phenol type epoxy resin; polyfunctionality such as ethoxylated isocyanurate type epoxy resin Heterocyclic epoxy resins; polyfunctional silicon-containing epoxy resins such as siloxane type epoxy resins;
Among these, from the viewpoint of transparency and heat resistance, a compound having at least one selected from the group consisting of an alicyclic structure, an aromatic ring structure, and a heterocyclic structure in the molecule is preferable. More preferred are functional alicyclic alcohol glycidyl ethers; the above polyfunctional phenol glycidyl ethers; and the above polyfunctional heterocyclic epoxy resins.
These compounds can be used individually or in combination of 2 or more types.

The reaction between the epoxy group and the carboxyl group proceeds even at room temperature without heating. If the reaction proceeds before the core pattern is formed by exposure and development, a crosslinked structure is formed and becomes insoluble in the developer. Therefore, it is necessary to suppress the reaction during storage.
The epoxy equivalent of (C) component becomes like this. Preferably it is 250-1000 g / eq, More preferably, it is 260-750 g / eq, More preferably, it is 270-500 g / eq. When it is 250 g / eq or more, the heat resistance can be improved, and an epoxy group that can occur during storage of a resin composition for forming an optical waveguide and a resin film for forming an optical waveguide made of the resin composition, which will be described later, The reaction of the carboxyl group of the component (A) can be suppressed, and the storage stability can be improved. On the other hand, it is preferably 1000 g / eq or less because a crosslinked structure can be sufficiently formed, heat resistance can be improved, and solubility in a developing solution is improved.

As an epoxy resin whose epoxy equivalent belongs to the above preferred range, commercially available products such as “Epicoat YX8034” (epoxy equivalent 290 g / eq), “Epicoat YL7170” (epoxy equivalent 1000 g / eq) manufactured by Japan Epoxy Resins Co., Ltd. Hydrogenated bisphenol A type epoxy resin such as “Epototo ST-4000D” (epoxy equivalent 700 g / eq) manufactured by Toto Kasei Co., Ltd .; “Epicoat 834” (epoxy equivalent 250 g / eq) manufactured by Japan Epoxy Resin Co., Ltd., “ “Epicoat 1001” (epoxy equivalent 475 g / eq), “Epicoat 1002” (epoxy equivalent 650 g / eq), “Epicoat 1003” (epoxy equivalent 720 g / eq), “Epicoat 1003F” (epoxy equivalent 750 g / eq), “Epicoat 1004F” ”(Epoxy equivalent 810 g / eq),“ Epicoat 1055 ”(epoxy equivalent 850 g / eq),“ Epicoat 1004 ”(epoxy equivalent 925 g / eq),“ Epicoat 1004AF ”(epoxy equivalent 925 g / eq),“ Epicoat 1004F ”( Epoxy equivalent 925 g / eq), “Epicoat 1005F” (epoxy equivalent 1000 g / eq), “Epicoat 1006FS” (epoxy equivalent 1000 g / eq), “Epototo YD-134” (epoxy equivalent 250 g / eq) manufactured by Tohto Kasei Co., Ltd. "Epototo YD-011" (epoxy equivalent 475 g / eq), "Epototo YD-7011R" (epoxy equivalent 475 g / eq), "Epototo YD-901" (epoxy equivalent 475 g / eq), "Epototo YD-012" ( Epoxy 650 g / eq), “Epototo YD-902” (epoxy equivalent 650 g / eq), “Epototo YD-903N” (epoxy equivalent 810 g / eq), “Epototo YD-013” (epoxy equivalent 850 g / eq), “Epototo YD -014 "(epoxy equivalent 950 g / eq)," Epototo YD-904 "(epoxy equivalent 950 g / eq), and other bisphenol A type epoxy resins;" Rikaresin BEO-60E "(Epoxy equivalent 365 g / manufactured by Shin Nippon Rika Co., Ltd.) eq) and other ethoxylated bisphenol A type epoxy resins; “Epicoat 4004P” manufactured by Japan Epoxy Resin Co., Ltd. (epoxy equivalent 880 g / eq), “Epototo YDF-2001” manufactured by Toto Kasei Co., Ltd. (epoxy equivalent 475 g / eq) , “Epototo YDF-2004” (Epo Bisphenol F type epoxy resin such as xy equivalent 950 g / eq); “Epototo YDB-360” (epoxy equivalent 360 g / eq), “Epototo YDB-400” (epoxy equivalent 400 g / eq), “Epototo” Tetrabromobisphenol A type epoxy resin such as “YDB-405” (epoxy equivalent 580 g / eq); Biphenyl type epoxy resin such as “Epiclon EXA-7400” (epoxy equivalent 290 g / eq) manufactured by DIC Corporation; Nagase ChemteX ( “ONCOAT EX-1060” (epoxy equivalent 265 g / eq), “ONCOAT EX-1012” (epoxy equivalent 292 g / eq), “ONCOAT EX-1020” (epoxy equivalent 305 g / eq), “ON” Coat EX-1050 "(epoxy equivalent 312 g / e ), Fluorene bisphenol type epoxy resins such as “ONCOAT EX-1051” (epoxy equivalent 315 g / eq); “NC-3000” (epoxy equivalent 275 g / eq), “NC-3000-H” manufactured by Nippon Kayaku Co., Ltd. "Epoxylon HP-5000" (epoxy equivalent 250g / eq), "Epiclon EXA-9900" (epoxy equivalent 275g / eq) manufactured by DIC Corporation Naphthalene / cresol novolak type epoxy resins such as “BREN-105” (epoxy equivalent 275 g / eq), “BREN-S” (epoxy equivalent 285 g / eq), “BREN-304” (epoxy) manufactured by Nippon Kayaku Co., Ltd. Bromophenol novolac type epoxies such as equivalents 310 g / eq) Dicyclopentadiene / phenolic epoxy resin such as “Epicron HP-7200” (epoxy equivalent 260 g / eq), “Epicron HP-7200H” (epoxy equivalent 280 g / eq) manufactured by DIC Corporation; Nagase ChemteX ( Ethoxylated isocyanurate type epoxy resin such as “Denacol EX-301” (epoxy equivalent 270 g / eq) manufactured by KK; “Epicron EXA-4850-1000” (epoxy equivalent 350 g / eq), “Epicron EXA” manufactured by DIC Corporation -4822 "(epoxy equivalent 390 g / eq)," Epiclon EXA-4816 "(epoxy equivalent 400 g / eq)," Epiclon EXA-4850-150 "(epoxy equivalent 450 g / eq), etc .; “Epico” manufactured by Resin Co., Ltd. For example, flexible epoxy resins such as "Etecoat 7175-500" (epoxy equivalent 490 g / eq) and "Epicoat 7175-500" (epoxy equivalent 490 g / eq).
In addition, the value of the epoxy equivalent described here is a value reported in a catalog or the like.

<(D) Radical polymerization initiator>
The resin composition for forming an optical waveguide of the present invention contains (D) a radical polymerization initiator. By blending component (D), radical polymerization of component (B) is initiated by irradiation with actinic rays such as heat, ultraviolet rays or visible rays, and the resin composition can be cured.
When the component (D) does not include the component (E), the amount of the component (A) to the component (C) is preferably 0.01 to 10 parts by mass, more preferably 0. It is 05-7 mass parts, More preferably, it is 0.1-5 mass parts. When it is 0.01 parts by mass or more, curing is sufficient, and when it is 10 parts by mass or less, transparency is improved, which is preferable.
Moreover, the compounding quantity of (D) component in the case of containing (E) component from the viewpoint similar to the above, Preferably it is 0 with respect to 100 mass parts of total amounts of (A)-(C) and (E) component. 0.01 to 10 parts by mass, more preferably 0.05 to 7 parts by mass, and still more preferably 0.1 to 5 parts by mass.

The component (D) is not particularly limited as long as it initiates radical polymerization by heating or irradiation with actinic rays such as ultraviolet rays and visible rays, and examples thereof include thermal radical polymerization initiators and photoradical polymerization initiators. It is done.
There is no restriction | limiting in particular as a thermal radical polymerization initiator, The thing similar to the thermal radical polymerization initiator used when synthesize | combining the said (meth) acrylic polymer can be mentioned suitably.
Among them, diacyl peroxide, peroxyester, and azo compound are preferable from the viewpoints of curability, transparency, and heat resistance.

The radical photopolymerization initiator is not particularly limited as long as radical polymerization is initiated by irradiation with actinic rays such as ultraviolet rays and visible rays. For example, 2,2-dimethoxy-1,2-diphenylethane-1- Benzoinketals such as ON; 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2- Α-hydroxy ketones such as methyl-1-propan-1-one and 2-hydroxy-1- {4 [4- (2-hydroxy-2-methylpropionyl) benzyl] phenyl} -2-methylpropan-1-one Methyl phenylglyoxylate, ethyl phenylglyoxylate, 2- (2-hydroxyethyl acetate) ) Glyoxyesters such as ethyl, oxyphenylacetic acid 2- (2-oxo-2-phenylacetoxyethoxy) ethyl; 2-benzyl-2-dimethylamino-1- (4-morpholin-4-ylphenyl) -butane -1-one, 2-dimethylamino-2- (4-methylbenzyl) -1- (4-morpholin-4-ylphenyl) -butan-1-one, 1,2-methyl-1- [4- Α-amino ketones such as (methylthio) phenyl]-(4-morpholin) -2-ylpropan-1-one; 1,2-octanedione, 1- [4- (phenylthio), 2- (O-benzoyloxime) )], Oxime esters such as ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl], 1- (O-acetyloxime); Phosphine oxides such as 2,4,6-trimethylbenzoyl) phenylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide; 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (o-chlorophenyl) -4,5-di (methoxyphenyl) imidazole dimer, 2- (o-fluorophenyl) -4 2,5-diphenylimidazole dimer, 2- (o-methoxyphenyl) -4,5-diphenylimidazole dimer, 2- (p-methoxyphenyl) -4,5-diphenylimidazole dimer, etc. 4,5-triarylimidazole dimer; benzophenone, N, N′-tetramethyl Benzophenone compounds such as 4,4′-diaminobenzophenone, N, N′-tetraethyl-4,4′-diaminobenzophenone, 4-methoxy-4′-dimethylaminobenzophenone; 2-ethylanthraquinone, phenanthrenequinone, 2-tert- Butylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 2-methylanthraquinone, 1,4-naphthoquinone, 9 , 10-phenanthraquinone, 2-methyl-1,4-naphthoquinone, 2,3-dimethylanthraquinone and other quinone compounds; benzoin methyl ether, benzoin ethyl ether, benzoin phenyl ether and the like Benzoin ethers; benzoin compounds such as benzoin, methylbenzoin and ethylbenzoin; benzyl compounds such as benzyldimethyl ketal; acridine compounds such as 9-phenylacridine and 1,7-bis (9,9′-acridinylheptane): N— Examples include phenylglycine and coumarin.
In the 2,4,5-triarylimidazole dimer, the aryl group substituents at the two triarylimidazole sites may give the same and symmetric compounds, but give differently asymmetric compounds. May be.
Among these, from the viewpoint of curability and transparency, the α-hydroxyketone; the glyoxyester; the oxime ester; and the phosphine oxide are preferable.
The above radical polymerization initiators (such as a thermal radical polymerization initiator and a photo radical polymerization initiator) can be used alone or in combination of two or more kinds, and may be used in combination with an appropriate sensitizer.

<(E) (Meth) acrylate not having urethane bond>
It is preferable that the resin composition for forming an optical waveguide of the present invention further includes (E) (meth) acrylate having no urethane bond.
(E) The compounding quantity of a component becomes like this. Preferably it is 5-80 mass% with respect to the total amount of (A)-(C) and (E) component, More preferably, it is 10-60 mass%, More preferably, it is 15-40. % By mass. When it is 5% by mass or more, it reacts with the component (B) to form a sufficient cross-linked structure, so that the heat resistance is good, and when it is 80% by mass or less, the toughness is good and it does not become brittle. preferable.

  The component (E) is not particularly limited, and any of monofunctional (meth) acrylate, bifunctional (meth) acrylate, and trifunctional or higher (meth) acrylate can be used.

  There is no restriction | limiting in particular as monofunctional (meth) acrylate, For example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) Acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, butoxyethyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, heptyl (meth) acrylate , Octyl heptyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, undecyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (meth) acrylate Tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, octadecyl (meth) acrylate, behenyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3- Chloro-2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, ethoxypolyethylene glycol (meth) acrylate, methoxypolypropylene glycol (meth) acrylate, ethoxypolypropylene glycol (meth) Acrylates, aliphatic (meth) acrylates such as mono (2- (meth) acryloyloxyethyl) succinate, ethoxy of these , These propoxylated compounds, these ethoxylated propoxylated compounds, and their caprolactone modified products; cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) Cycloaliphatic (meth) acrylates such as acrylate, isobornyl (meth) acrylate, mono (2- (meth) acryloyloxyethyl) tetrahydrophthalate, mono (2- (meth) acryloyloxyethyl) hexahydrophthalate, and ethoxylation of these , These propoxylated compounds, these ethoxylated propoxylated compounds, and their caprolactone modified products; phenyl (meth) acrylate, benzyl (meth) acrylate, o-biphenyl (meth) acrylate, 1-naphthy (Meth) acrylate, 2-naphthyl (meth) acrylate, phenoxyethyl (meth) acrylate, p-cumylphenoxyethyl (meth) acrylate, o-phenylphenoxyethyl (meth) acrylate, 1-naphthoxyethyl (meth) acrylate, 2-naphthoxyethyl (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, nonylphenoxypolyethylene glycol (meth) acrylate, phenoxypolypropylene glycol (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, 2-hydroxy- 3- (o-phenylphenoxy) propyl (meth) acrylate, 2-hydroxy-3- (1-naphthoxy) propyl (meth) acrylate, 2-hydroxy Aromatic (meth) acrylates such as 3- (2-naphthoxy) propyl (meth) acrylate, ethoxylated products thereof, propoxylated products thereof, ethoxylated propoxylated products thereof, and modified caprolactone products thereof; Tetrahydrofurfuryl (meth) acrylate, N- (meth) acryloyloxyethyl tetrahydrophthalimide, N- (meth) acryloyloxyethyl hexahydrophthalimide, isocyanuric acid mono (meth) acrylate, 2- (meth) acryloyloxyethyl-N- Examples thereof include heterocyclic (meth) acrylates such as carbazole, ethoxylated products thereof, propoxylated products thereof, ethoxylated propoxylated products thereof, and caprolactone modified products thereof.

  Among these, from the viewpoints of transparency and heat resistance, a compound having at least one selected from the group consisting of an alicyclic structure, an aromatic ring structure, and a heterocyclic structure in the molecule is preferable. Specifically, cyclohexyl ( (Meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, cycloaliphatic (meth) acrylate such as isobornyl (meth) acrylate, ethoxylated products thereof, propoxylated products thereof, these Ethoxylated propoxy compounds and their caprolactone modified products: benzyl (meth) acrylate, phenoxyethyl (meth) acrylate, p-cumylphenoxyethyl (meth) acrylate, o-phenylphenoxyethyl (meth) acrylate, phenoxypolyethylene glycol (Meta) Acry , Aromatic (meth) acrylates such as phenoxy polypropylene glycol (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, 2-hydroxy-3- (o-phenylphenoxy) propyl (meth) acrylate, These ethoxylated compounds, these propoxylated compounds, these ethoxylated propoxylated compounds, and these caprolactone modified products; N- (meth) acryloyloxyethyl tetrahydrophthalimide, N- (meth) acryloyloxyethyl hexahydrophthalimide, Heterocyclic (meth) acrylates such as isocyanuric acid mono (meth) acrylate and 2- (meth) acryloyloxyethyl-N-carbazole, ethoxylated compounds thereof, propoxylated compounds thereof, and ethoxylated propoxides thereof Shikakarada, and their caprolactone modified products are more preferred. The ethoxylated product, propoxylated product, ethoxylated propoxylated product, and caprolactone-modified product are as described above.

  There is no restriction | limiting in particular as bifunctional (meth) acrylate, For example, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, polyethyleneglycol di (meth) acrylate, propylene glycol di (meth) acrylate, dipropylene glycol Di (meth) acrylate, polypropylene glycol di (meth) acrylate, 1,3-propanediol di (meth) acrylate, 2-methyl-1,3-propanediol di (meth) acrylate, 2-butyl-2-ethyl- 1,3-propanediol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 3-methyl-1,5-pentanediol di (meth) acrylate, 1 , -Aliphatic (meth) acrylates such as hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, 1,10-decanediol di (meth) acrylate, glycerin di (meth) acrylate, and the like Ethoxylated compounds, these propoxylated compounds, these ethoxylated propoxylated compounds, and their caprolactone modified products; ethylene glycol type epoxy di (meth) acrylate, diethylene glycol type epoxy di (meth) acrylate, polyethylene glycol type epoxy di (meth) acrylate , Propylene glycol type epoxy di (meth) acrylate, dipropylene glycol type epoxy di (meth) acrylate, polypropylene glycol type epoxy di (meth) acrylate, 1,3-propanedio Type epoxy di (meth) acrylate, 2-methyl-1,3-propanediol type epoxy di (meth) acrylate, 2-butyl-2-ethyl-1,3-propanediol type epoxy di (meth) acrylate, 1,4- Butanediol type epoxy di (meth) acrylate, neopentyl glycol type epoxy di (meth) acrylate, 3-methyl-1,5-pentanediol type epoxy di (meth) acrylate, 1,6-hexanediol type epoxy di (meth) acrylate, 1 , 9-nonanediol type epoxy di (meth) acrylate, aliphatic epoxy (meth) acrylate such as 1,10-decanediol type epoxy di (meth) acrylate; cyclohexanedimethanol di (meth) acrylate, tricyclodecane dimethanol di ( Meta ) Aliphatic (meth) acrylates such as acrylate, hydrogenated bisphenol A di (meth) acrylate, hydrogenated bisphenol F di (meth) acrylate, ethoxylated products thereof, propoxylated products thereof, ethoxylated propoxylated products thereof And their caprolactone-modified products: cyclohexanedimethanol type epoxy di (meth) acrylate, tricyclodecane dimethanol type epoxy di (meth) acrylate, hydrogenated bisphenol A type epoxy di (meth) acrylate, hydrogenated bisphenol F type epoxy di (meth) ) Alicyclic epoxy (meth) acrylates such as acrylate; hydroquinone di (meth) acrylate, resorcinol di (meth) acrylate, catechol di (meth) acrylate, bisphenol A di (meth) acrylate, vinyl Aromatic (meth) acrylates such as phenol F di (meth) acrylate, bisphenol AF di (meth) acrylate, biphenol di (meth) acrylate, fluorene bisphenol di (meth) acrylate, ethoxylated products thereof, propoxylated products thereof , Ethoxylated propoxy compounds thereof, and modified caprolactone thereof; hydroquinone type epoxy di (meth) acrylate, resorcinol type epoxy di (meth) acrylate, catechol type epoxy di (meth) acrylate, bisphenol A type epoxy di (meth) acrylate, bisphenol F type epoxy di (meth) acrylate, bisphenol AF type epoxy di (meth) acrylate, biphenol type epoxy di (meth) acrylate, fluorene bisphenol Type epoxy di (meth) acrylate and other aromatic epoxy (meth) acrylates; bis (2- (meth) acryloyloxyethyl) (2-hydroxyethyl) isocyanurate and other heterocyclic (meth) acrylates, and ethoxylation of these , Propoxylated compounds thereof, ethoxylated propoxylated compounds thereof, and caprolactone modified products thereof; heterocyclic (meth) acrylates such as monoisocyanuric acid type epoxy di (meth) acrylate and the like. The ethoxylated product, propoxylated product, ethoxylated propoxylated product, and caprolactone-modified product are as described above.

  Among these, from the viewpoint of transparency and heat resistance, a compound having at least one selected from the group consisting of an alicyclic structure, an aromatic ring structure, and a heterocyclic structure in the molecule is preferable. Cyclic (meth) acrylates, ethoxylated products thereof, propoxylated products thereof, ethoxylated propoxylated products thereof, and caprolactone modified products thereof; the above alicyclic epoxy (meth) acrylates; bisphenol A di (meth) Aromatic (meth) acrylates such as acrylate, bisphenol F di (meth) acrylate, bisphenol AF di (meth) acrylate, biphenol di (meth) acrylate, fluorene bisphenol di (meth) acrylate, ethoxylated products thereof, propoxy compounds thereof , Their ethoxylated propoxylates, and These modified caprolactones: bisphenol A type epoxy di (meth) acrylate, bisphenol F type epoxy di (meth) acrylate, bisphenol AF type epoxy di (meth) acrylate, biphenol type epoxy di (meth) acrylate, fluorene bisphenol type epoxy di (meth) acrylate More preferred are aromatic epoxy (meth) acrylates such as the above-mentioned heterocyclic (meth) acrylates, ethoxylated products thereof, propoxylated products thereof, ethoxylated propoxylated products, and modified caprolactone products thereof.

The trifunctional or higher functional (meth) acrylate is not particularly limited, and examples thereof include trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, and ditrimethylolpropane tetra (meth) acrylate. , Aliphatic (meth) acrylates such as dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, ethoxylated forms thereof, propoxylated forms thereof, ethoxylated propoxylated forms thereof, and these Modified caprolactone; aromatic epoxy (meth) acrylate such as phenol novolac type epoxy (meth) acrylate, cresol novolac type epoxy poly (meth) acrylate; tris (2- (meta Heterocyclic (meth) acrylates such as (acryloyloxyethyl) isocyanurate, ethoxylated forms thereof, propoxylated forms thereof, ethoxylated propoxylated forms thereof, and caprolactone modified forms thereof; isocyanuric acid type epoxy tri ( Examples include heterocyclic (meth) epoxy acrylates such as (meth) acrylates. The ethoxylated product, propoxylated product, ethoxylated propoxylated product, and caprolactone-modified product are as described above.
Among these, from the viewpoint of transparency and heat resistance, a compound having at least one selected from the group consisting of an alicyclic structure, an aromatic ring structure, and a heterocyclic structure in the molecule is preferable, specifically, More preferred are aromatic epoxy (meth) acrylates; heterocyclic (meth) acrylates; isocyanuric acid type epoxy (meth) acrylates.
The above (meth) acrylates having no urethane bond can be used alone or in combination of two or more, and can also be used in combination with other polymerizable compounds.

<(F) Curing accelerator>
The resin composition for forming an optical waveguide of the present invention preferably further contains (F) a curing accelerator.
When the component (F) does not include the component (E), the amount of the component (A) to the component (C) is preferably 0.01 to 10 parts by mass, more preferably 0. It is 05-7 mass parts, More preferably, it is 0.1-5 mass parts. When the content is 0.01 parts by mass or more, the reaction between the carboxyl group of the component (A) and the epoxy group of the component (C) can be promoted to form a sufficient cross-linked structure. When it exists, since reaction of the carboxyl group of (A) component and the epoxy group component of (C) component can be suppressed and storage stability can be improved, it is preferable.
Moreover, the compounding quantity of (F) component in the case of containing (E) component from the same viewpoint as the above, Preferably it is 0 with respect to 100 mass parts of total amounts of (A)-(C) and (E) component. 0.01 to 10 parts by mass, more preferably 0.05 to 7 parts by mass, and still more preferably 0.1 to 5 parts by mass.

The component (F) is not particularly limited as long as it is a compound that promotes the reaction between the carboxyl group of the component (A) and the epoxy group of the component (C). For example, tri-n-butylamine, benzylmethylamine, methyl Secondary amines such as aniline; triethylamine, tri-n-propylamine, triisopropylamine, tri-n-butylamine, diethylisopropylamine, benzyldimethylamine, N, N-dimethylaniline, N, N, N ′, N ′ -Tertiary amines such as tetramethylethylenediamine; pyrrolidine, N-methylpyrrolidine, piperidine, N-methylpiperidine, morpholine, N-methylmorpholine, piperazine, N, N'-dimethylpiperazine, 1,4-diazabicyclo [2.2 .2] Octane, 1,5-diazabicyclo [4.3.0] nona-5 Cyclic amines such as ene and 1,8-diazabicyclo [5.4.0] undec-7-ene; 2-methylimidazole, 2-ethylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-phenylimidazole 1,2-dimethylimidazole, 2-ethyl-1-methylimidazole, 1,2-diethylimidazole, 1-ethyl-2-methylimidazole, 2-ethyl-4-methylimidazole, 4-ethyl-2-methylimidazole 2-phenyl-4-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl- 2-Ethyl-4-methylimida 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo [1,2-a] benzimidazole, 2, 4-diamino-6- [2'-methylimidazolyl- (1 ')] ethyl-s-triazine, 2,4-diamino-6- [2'-undecylimidazolyl- (1')] ethyl-s-triazine Imidazole compounds such as 2,4-diamino-6- [2′-ethyl-4′-methylimidazolyl- (1 ′)] ethyl-s-triazine; trimellitic acid adducts of the imidazole compounds; isocyanurates of the imidazole compounds Acid adducts; hydrobromic acid adducts of the above imidazole compounds; tetra-n-butylammonium chloride, tetra-n-butylammonium bromide Arm, iodide tetra -n- butylammonium, benzyltrimethylammonium chloride, bromide, benzyltrimethylammonium, and the like quaternary ammonium salts such as benzyl iodide trimethylammonium.
Among these, from the viewpoint of transparency and curability, the imidazole compound; the trimellitic acid adduct of the imidazole compound; and the isocyanuric acid adduct of the imidazole compound are preferable.
These compounds can be used individually or in combination of 2 or more types.

<Other ingredients>
In the resin composition for forming an optical waveguide of the present invention, an antioxidant, an anti-yellowing agent, an ultraviolet absorber, a visible light absorber, a colorant, a plasticizer, a stabilizer, a filler, etc., as necessary. You may add what is called an additive in the ratio which does not have a bad influence on the effect of this invention.

<Organic solvent>
The resin composition for forming an optical waveguide of the present invention may be diluted with a suitable organic solvent and used as a resin varnish for forming an optical waveguide. The solid content concentration in the resin varnish is preferably 10 to 80% by mass, more preferably 15 to 75% by mass, and still more preferably 20 to 70% by mass.
The organic solvent is not particularly limited as long as it is a solvent capable of dissolving the resin composition, and the same organic solvents as those used as a reaction solvent capable of dissolving the above (meth) acrylic polymer can be preferably exemplified. . These organic solvents can be used individually or in combination of 2 or more types.

<Preparation of resin composition for forming optical waveguide>
When the resin composition for forming an optical waveguide is prepared, it is preferably mixed by stirring. Although there is no restriction | limiting in particular in the stirring method, From a viewpoint of stirring efficiency, stirring using a propeller is preferable. Although the rotational speed of the propeller at the time of stirring does not have a restriction | limiting in particular, Preferably it is 10-1,000 rpm, More preferably, it is 50-800 rpm, More preferably, it is 100-500 rpm. When it is 10 rpm or more, each component is sufficiently mixed, and when it is 1,000 rpm or less, entrainment of bubbles due to rotation of the propeller is preferably reduced.
The stirring time is not particularly limited, but is preferably 1 to 24 hours. When the stirring time is 1 hour or more, the respective components are sufficiently mixed, and when it is 24 hours or less, the preparation time can be shortened and productivity is improved, which is preferable.

  The prepared resin composition for forming an optical waveguide is preferably filtered using a filter. The pore size of the filter used is preferably 50 μm or less, more preferably 30 μm or less, and still more preferably 10 μm or less. It is preferable to use a filter having a pore size of 50 μm or less because large foreign matters and the like are removed so that no repelling occurs at the time of coating, and light scattering is suppressed and transparency is not impaired.

  The prepared optical waveguide forming resin composition or resin varnish is preferably degassed under reduced pressure. Although there is no restriction | limiting in particular in the defoaming method, For example, the method of using a vacuum pump, a bell jar, and the defoaming apparatus with a vacuum apparatus is mentioned. Although the pressure at the time of pressure reduction does not have a restriction | limiting in particular, The pressure which the low boiling point component contained in a resin composition does not boil is preferable. The vacuum degassing time is not particularly limited but is preferably 3 to 60 minutes. If it is 3 minutes or longer, bubbles dissolved in the resin composition can be removed, and if it is 60 minutes or less, the organic solvent contained in the resin composition does not volatilize and the defoaming time is shortened. This is preferable because productivity is improved.

[Resin film for optical waveguide formation]
The resin film for forming an optical waveguide of the present invention is formed using the resin composition for forming an optical waveguide, and includes the above components (A) to (D), and further blended as necessary (E) and (F) components. It can manufacture easily by apply | coating the resin composition for optical waveguide formation containing to a suitable support film, and forming a resin layer. When using a resin varnish for forming an optical waveguide diluted with an organic solvent, the resin layer can be formed by applying the resin varnish to a support film and removing the organic solvent using a method such as drying. .

The support film is not particularly limited. For example, polyesters such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; polyolefins such as polyethylene and polypropylene; polycarbonates, polyamides, polyimides, polyamideimides, polyetherimides, polyether sulfides, Examples include polyethersulfone, polyetherketone, polyphenylene ether, polyphenylene sulfide, polyarylate, polysulfone, and liquid crystal polymer.
Among these, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polypropylene, polycarbonate, polyamide, polyimide, polyamideimide, polyphenylene ether, polyphenylene sulfide, polyarylate, and polysulfone are preferable from the viewpoints of flexibility and toughness.
In addition, from the viewpoint of improving the peelability from the resin layer, a support film that has been subjected to a release treatment with a silicone compound, a fluorine-containing compound, or the like may be used as necessary.

  Although the thickness of a support film is suitably changed according to the softness | flexibility made into the objective, Preferably it is 3-250 micrometers, More preferably, it is 5-200 micrometers, More preferably, it is 7-150 micrometers. If it is 3 μm or more, the film strength is sufficient, and if it is 250 μm or less, it is preferable because sufficient flexibility can be obtained.

  The thickness of the resin layer after drying is not particularly limited, but is preferably 5 to 500 μm, more preferably 7 to 450 μm, and still more preferably 10 to 400 μm. When the thickness is 5 μm or more, since the thickness is sufficient, the strength of the resin film or a cured product thereof is sufficient, and when it is 500 μm or less, the drying can be sufficiently performed without increasing the amount of residual solvent in the resin film, Since it does not foam when the hardened | cured material of a resin film is heated, it is preferable.

  The optical waveguide forming resin film may have a three-layer structure including a support film, a resin layer, and a protective film by attaching a protective film on the resin layer as necessary.

  The protective film is not particularly limited, but from the viewpoint of flexibility and toughness, polyesters such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; polyolefins such as polyethylene and polypropylene are preferable. In addition, from the viewpoint of improving the peelability from the resin layer, a film that has been subjected to a release treatment with a silicone compound, a fluorine-containing compound, or the like may be used as necessary.

  The thickness of the protective film is appropriately changed depending on the intended flexibility, but is preferably 10 to 250 μm, more preferably 15 to 200 μm, and still more preferably 20 to 150 μm. When it is 10 μm or more, the film strength is sufficient, and when it is 250 μm or less, it is preferable because sufficient flexibility can be obtained.

  The resin film for forming an optical waveguide thus obtained can be easily stored, for example, by winding it into a roll. Moreover, a roll-shaped film can be cut out into a suitable size and stored in a sheet shape.

Hereinafter, application examples of the resin film for forming an optical waveguide of the present invention will be described.
The support film used in the process of manufacturing the core portion forming resin film is not particularly limited as long as it can transmit the actinic ray for exposure used for core pattern formation. For example, the above-described optical waveguide forming resin film The thing similar to what was described as a specific example of a support film can be mentioned suitably.
Among these, polyesters and polyolefins are preferable from the viewpoints of the transmittance of actinic rays for exposure, flexibility, and toughness. Furthermore, a highly transparent support film is more preferable from the viewpoint of improving the transmittance of exposure actinic rays and reducing the side wall roughness of the core pattern. Examples of such a highly transparent support film include commercially available “Cosmo Shine A1517”, “Cosmo Shine A4100” manufactured by Toyobo Co., Ltd., “Lumirror FB50” manufactured by Toray Industries, Inc., and the like.
In addition, from the viewpoint of improving the peelability from the resin layer, a film that has been subjected to a release treatment with a silicone compound, a fluorine-containing compound, or the like may be used as necessary.

  The thickness of the support film of the core portion forming resin film is preferably 5 to 50 μm, more preferably 10 to 40 μm, and still more preferably 15 to 30 μm. When the thickness is 5 μm or more, the strength as a support is sufficient, and when the thickness is 50 μm or less, the gap between the photomask and the core portion forming resin layer is not increased when the core pattern is formed, and the pattern resolution is improved.

[Optical waveguide]
Hereinafter, the optical waveguide of the present invention will be described.
A sectional view of the optical waveguide is shown in FIG. The optical waveguide 1 is formed on a base material 5 and has a core part 2 made of a core part-forming resin composition having a high refractive index, and a lower cladding layer 4 made of a resin composition for forming a cladding layer having a low refractive index. And the upper clad layer 3.
The resin composition for forming an optical waveguide or the resin film for forming an optical waveguide of the present invention is preferably used for at least one of the lower cladding layer 4, the core portion 2, and the upper cladding layer 3 of the optical waveguide 1. By using the resin film for forming an optical waveguide of the present invention, the flatness of each layer, the interlayer adhesion between the clad and the core, and the resolution (correspondence between fine lines or narrow lines) when forming the optical waveguide core pattern are further improved. It is possible to form a fine pattern with excellent flatness and a small line width and line spacing.

  There is no restriction | limiting in particular as a material of the base material 5, For example, a glass epoxy resin substrate, a ceramic substrate, a glass substrate, a silicon substrate, a plastic substrate, a metal substrate, a substrate with a resin layer, a substrate with a metal layer, a plastic film, a resin layer And a plastic film with a metal layer and a plastic film with a metal layer.

The optical waveguide 1 may be a flexible optical waveguide by using a base material having flexibility and toughness as the base material 5, for example, a support film of the resin film for forming an optical waveguide as a base material. 5 may function as a protective film for the optical waveguide 1. By disposing the protective film, the flexibility and toughness of the protective film can be imparted to the optical waveguide 1, and the optical waveguide 1 is not subjected to dirt or scratches, so that the ease of handling is improved.
From the above viewpoint, the base material 5 having a function as a protective film is disposed outside the upper cladding layer 3 as shown in FIG. 1B, or the lower cladding layer 4 as shown in FIG. And the base material 5 which has a function as a protective film may be arrange | positioned on the outer side of both of the upper clad layers 3.
If the optical waveguide 1 has sufficient flexibility and toughness, the substrate 5 having a function as a protective film may not be disposed as shown in FIG.

The thickness of the lower clad layer 4 is not particularly limited, but is preferably 2 to 200 μm. When the thickness is 2 μm or more, it becomes easy to confine propagating light inside the core, and when the thickness is 200 μm or less, the thickness of the entire optical waveguide 1 is not too large. The thickness of the lower cladding layer 4 is a value from the boundary between the core portion 2 and the lower cladding layer 4 to the lower surface of the lower cladding layer 4.
Although there is no restriction | limiting in particular about the thickness of the resin film for lower clad layer formation, It adjusts so that the thickness of the lower clad layer 4 after hardening may become said range.

  The height of the core part 2 is not particularly limited, but is preferably 10 to 150 μm, more preferably 15 to 130 μm, and still more preferably 20 to 120 μm. When it is 10 μm or more, the alignment tolerance is not reduced in the coupling with the light emitting / receiving element or the optical fiber after the optical waveguide is formed, and when it is 150 μm or less, the light receiving / emitting element or the optical fiber after the optical waveguide is formed The coupling is preferable because the coupling efficiency does not decrease. In addition, there is no restriction | limiting in particular about the thickness of the resin film for core part formation, It adjusts so that the height of the core part after hardening may become said range.

  The thickness of the upper clad layer 3 is not particularly limited as long as the core portion 2 can be embedded, but the thickness after drying is preferably 12 to 500 μm. The thickness of the upper clad layer 3 may be the same as or different from the thickness of the lower clad layer 4 formed first, but is thicker than the thickness of the lower clad layer 4 from the viewpoint of embedding the core portion 2. It is preferable. The thickness of the upper cladding layer 3 is a value from the boundary between the core portion 2 and the lower cladding layer 4 to the upper surface of the upper cladding layer 3.

  In the optical waveguide of the present invention, the light propagation loss in a light source having a wavelength of 850 nm is preferably 0.3 dB / cm or less, more preferably 0.2 dB / cm or less, and further preferably 0.1 dB / cm or less. When it is 0.3 dB / cm or less, the loss of light becomes small and the strength of the transmission signal becomes sufficient, which is preferable.

In the optical waveguide of the present invention, the light propagation loss in a light source with a wavelength of 850 nm after 1000 hours of a high-temperature and high-humidity test at a temperature of 85 ° C. and a humidity of 85% is preferably 0.3 dB / cm from the same viewpoint as described above. Hereinafter, it is more preferably 0.2 dB / cm or less, and still more preferably 0.1 dB / cm or less.
The high-temperature and high-humidity storage test at a temperature of 85 ° C. and a humidity of 85% means a high-temperature and high-humidity storage test performed under conditions in accordance with the JPCA standard (JPCA-PE02-05-01S).

In the optical waveguide of the present invention, the light propagation loss in a light source with a wavelength of 850 nm after 1000 cycles of a temperature cycle test between −55 ° C. and 125 ° C. is preferably 0.3 dB / cm from the same viewpoint as described above. Hereinafter, it is more preferably 0.2 dB / cm or less, and still more preferably 0.1 dB / cm or less.
In addition, the temperature cycle test between temperature -55 degreeC and 125 degreeC means the temperature cycle test implemented on the conditions according to a JPCA standard (JPCA-PE02-05-01S).

In the optical waveguide of the present invention, the light propagation loss in a light source with a wavelength of 850 nm after three reflow tests at a maximum temperature of 265 ° C. is preferably 0.3 dB / cm or less, more preferably 0, from the same viewpoint as described above. .2 dB / cm or less, more preferably 0.1 dB / cm or less. If it is 0.3 dB / cm or less, the loss of light is reduced, the strength of the transmission signal is sufficient, and at the same time, component mounting by a reflow process can be performed, so that the application range can be widened.
The reflow test at the maximum temperature of 265 ° C. means a lead-free solder reflow test that is performed under conditions in accordance with the JEDEC standard (JEDEC JESD22A113E).

The optical waveguide of the present invention is excellent in transparency, environmental reliability, and heat resistance, and may be used as an optical transmission line of an optical module. Examples of the optical module include an optical waveguide with an optical fiber in which optical fibers are connected to both ends of the optical waveguide, an optical waveguide with a connector in which connectors are connected to both ends of the optical waveguide, and an opto-electrical device in which the optical waveguide and the printed wiring board are combined. Examples include a composite substrate, an optical / electrical conversion module that combines an optical waveguide and an optical / electrical conversion element that mutually converts an optical signal and an electrical signal, and a wavelength multiplexer / demultiplexer that combines an optical waveguide and a wavelength division filter.
In the photoelectric composite substrate, the printed wiring board to be combined is not particularly limited, and examples thereof include rigid substrates such as glass epoxy substrates and ceramic substrates; flexible substrates such as polyimide substrates and polyethylene terephthalate substrates.

[Production method of optical waveguide]
Hereinafter, the manufacturing method of the optical waveguide using the resin composition for optical waveguide formation of this invention and / or the resin film for optical waveguide formation is demonstrated.
The method for producing the optical waveguide of the present invention is not particularly limited. For example, the resin composition for forming an optical waveguide is formed on a substrate using a resin composition for forming an optical waveguide and / or a resin film for forming an optical waveguide. The method of forming and manufacturing is mentioned.

  The base material used in the present invention is not particularly limited, and is a glass epoxy resin substrate, a ceramic substrate, a glass substrate, a silicon substrate, a plastic substrate, a metal substrate, a substrate with a resin layer, a substrate with a metal layer, a plastic film, a resin layer. And a plastic film with a metal layer and a plastic film with a metal layer.

The method for forming the optical waveguide forming resin layer is not particularly limited. For example, using the optical waveguide forming resin composition, spin coating, dip coating, spraying, bar coating, roll coating, Examples of the coating method include a curtain coating method, a gravure coating method, a screen coating method, and an inkjet coating method.
When the resin composition for forming an optical waveguide is diluted with a suitable organic solvent, a step of drying may be added after forming the resin layer as necessary. There is no restriction | limiting in particular as a drying method, For example, heat drying, reduced pressure drying, etc. are mentioned. Moreover, you may use these together as needed.
As another method for forming the optical waveguide forming resin layer, there is a method of forming an optical waveguide forming resin film by a laminating method.
Among these, from the viewpoint that an optical waveguide having excellent flatness and having a fine pattern with a small line width and a small line pattern can be formed, a method of producing by a lamination method using a resin film for forming an optical waveguide is preferable.

Hereinafter, although the manufacturing method for forming the optical waveguide 1 using the resin film for optical waveguide formation for the lower clad layer 4, the core part 2, and the upper clad layer 3 will be described, the present invention is not limited to this. It is not a thing.
First, as a first step, a resin film for forming a lower clad layer is laminated on the substrate 5. There is no restriction | limiting in particular as a lamination | stacking method in a 1st process, For example, the method of laminating | stacking by crimping, heating using a roll laminator or a flat plate laminator, etc. are mentioned. The flat plate laminator in the present invention refers to a laminator in which a laminated material is sandwiched between a pair of flat plates and pressed by pressing the flat plate. For example, a vacuum pressurizing laminator can be suitably used. The heating temperature here is preferably 20 to 130 ° C. and the pressure bonding pressure is preferably 0.1 to 1.0 MPa, but these conditions are not particularly limited. When a protective film exists in the resin film for lower clad layer formation, it laminates | stacks, after removing a protective film.

  When laminating using a vacuum pressurizing laminator, a lower clad layer forming resin film may be temporarily pasted onto the substrate 5 in advance using a roll laminator. Here, from the viewpoint of improving adhesion and followability, it is preferable to perform temporary bonding while pressing, and when pressing, a laminator having a heat roll may be used while heating. In this case, the lamination temperature is preferably 20 to 150 ° C, more preferably 40 to 130 ° C. When it is 20 ° C. or higher, the adhesion between the resin film for forming the lower clad layer and the substrate 5 is improved, and when it is 150 ° C. or lower, the resin layer does not flow too much at the time of roll lamination, and the required film Thickness is obtained. The pressure during lamination is preferably 0.2 to 0.9 MPa, and the lamination speed is preferably 0.1 to 3 m / min, but these conditions are not particularly limited.

The lower clad layer forming resin layer laminated on the substrate 5 is cured by light and / or heat to form the lower clad layer 4. The removal of the support film of the lower clad layer forming resin film may be performed either before or after curing.
The irradiation amount of the actinic ray when the lower clad layer forming resin layer is cured by light is not particularly limited, but is preferably 0.1 to 5 J / cm ² . Moreover, when actinic rays permeate | transmit a base material, in order to make it harden | cure efficiently, the double-sided exposure machine which can irradiate actinic rays simultaneously from both surfaces can be used. Moreover, you may irradiate actinic light, heating. In addition, as a process before and behind photocuring, you may perform a 50-200 degreeC heat processing as needed.
The heating temperature for curing the resin layer for forming the lower cladding layer with heat is not particularly limited, but is preferably 50 to 200 ° C.

When the support film for the resin film for forming the lower cladding layer functions as a protective film for the optical waveguide 1, it is cured under the same conditions as described above by light and / or heat without laminating the resin film for forming the lower cladding layer. The lower cladding layer 4 may be formed.
The protective film for the resin film for forming the lower cladding layer may be removed before curing or after curing.

  As the second step, a core part-forming resin film is laminated on the lower cladding layer 4 by the same method as in the first step. Here, the core part forming resin layer is preferably made of a photosensitive resin composition that is designed to have a higher refractive index than the lower clad layer forming resin layer and can form a core pattern with actinic rays.

As a third step, the core portion 2 is exposed. The method for exposing the core part 2 is not particularly limited. For example, a method of irradiating an actinic ray in an image form through a negative photomask called artwork, without using a negative photomask using laser direct drawing. For example, a method of directly irradiating an actinic ray on an image can be mentioned.
The light source of the actinic ray is not particularly limited, and for example, a light source that effectively emits ultraviolet rays such as an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a mercury vapor arc lamp, a metal halide lamp, a xenon lamp, and a carbon arc lamp; Examples thereof include a light source that effectively emits visible light such as a light bulb and a solar lamp.

The irradiation amount of the actinic ray when exposing the core part 2 is preferably 0.01 to 10 J / cm ² , more preferably 0.03 to 5 J / cm ² , and still more preferably 0.05 to 3 J / cm ² . is there. When it is 0.01 J / cm ² or more, the curing reaction proceeds sufficiently and the core part 2 is not washed away by development, and when it is 10 J / cm ² or less, the core part 2 becomes thick due to excessive exposure. This is preferable because a fine pattern can be formed.
The exposure of the core part 2 may be performed through the support film of the core part forming resin film, or may be performed after removing the support film.

  Moreover, you may perform post-exposure heating as needed from a viewpoint of the resolution of the core part 2 and adhesive improvement after exposure. The post-exposure heating temperature is preferably 40 to 160 ° C., and the time from ultraviolet irradiation to post-exposure heating is preferably within 10 minutes, more preferably 30 seconds to 10 minutes. There is no limit.

As a 4th process, when exposed through the support film of the resin film for core part formation, this is removed and it develops using the developing solution suitable for the composition of resin for core part formation.
The development method is not particularly limited, and examples thereof include a spray method, a dip method, a paddle method, a spin method, a brushing method, and a scraping method. Moreover, you may use these image development methods together as needed.
The developer is not particularly limited, and examples thereof include an organic solvent, a semi-aqueous developer composed of an organic solvent and water, a water-based alkaline developer composed of an aqueous alkali solution, and a semi-aqueous alkaline developer composed of an alkaline aqueous solution and an organic solvent. It is done.
The development temperature is adjusted in accordance with the developability of the core portion forming resin layer.

  There is no restriction | limiting in particular as an organic solvent, For example, the thing similar to the organic solvent used for dilution of the said resin composition for optical waveguide formation is mentioned as a suitable solvent. In addition, an organic solvent can be used individually or in combination of 2 or more types. Further, a surface active agent, an antifoaming agent, or the like may be mixed in the organic solvent.

The quasi-aqueous developer is not particularly limited as long as it is composed of one or more organic solvents and water.
The concentration of the organic solvent is preferably 5 to 90% by mass. Further, a small amount of a surfactant, an antifoaming agent or the like may be mixed in the semi-aqueous developer.

There is no restriction | limiting in particular as a base of aqueous alkali solution, For example, Alkali metal hydroxides, such as lithium hydroxide, sodium hydroxide, potassium hydroxide; Alkali metal carbonates, such as lithium carbonate, sodium carbonate, potassium carbonate; Hydrogen carbonate Alkali metal bicarbonates such as lithium, sodium bicarbonate and potassium bicarbonate; alkali metal phosphates such as potassium phosphate and sodium phosphate; alkali metal pyrophosphates such as sodium pyrophosphate and potassium pyrophosphate; tetraboric acid Sodium salts such as sodium and sodium metasilicate; ammonium salts such as ammonium carbonate and ammonium hydrogen carbonate; tetramethylammonium hydroxide, triethanolamine, ethylenediamine, diethylenetriamine, 2-amino-2-hydroxymethyl-1,3-propanedio Le, organic bases such as 1,3-diamino-propanol-2-morpholine.
These bases can be used alone or in combination of two or more.
The pH of the aqueous alkaline developer is preferably 9-14. Further, a surfactant, an antifoaming agent or the like may be mixed in the aqueous alkaline developer.

The quasi-aqueous alkaline developer is not particularly limited as long as it comprises an aqueous alkali solution and one or more organic solvents. In addition, there is no restriction | limiting in particular in the base and organic solvent of alkali aqueous solution, The above-mentioned base and organic solvent of alkaline aqueous solution are mentioned as a suitable thing.
The pH of the quasi-aqueous alkaline developer is preferably as low as possible within a range where development can be sufficiently performed. Specifically, the pH is preferably 8 to 13, and more preferably 9 to 12.
The concentration of the organic solvent is preferably 5 to 90% by mass. Further, a small amount of a surfactant, an antifoaming agent or the like may be mixed in the semi-aqueous alkaline developer.

As the processing after development, the organic solvent, the semi-aqueous cleaning liquid, or water may be used as necessary. An organic solvent can be used individually or in combination of 2 or more types. In the semi-aqueous cleaning liquid, the concentration of the organic solvent is preferably 5 to 90% by mass.
The cleaning method is not particularly limited, and examples thereof include a spray method, a dipping method, a paddle method, a spin method, a brushing method, and a scraping method. Moreover, you may use these washing | cleaning methods together as needed. The washing temperature is adjusted in accordance with the developability of the core portion forming resin layer.

As processing after development or washing, exposure and / or heating may be performed as necessary from the viewpoint of improving the curability and adhesion of the core portion 2. The heating temperature is preferably 40 to 200 ° C., and the irradiation amount of active light is preferably 0.01 to 10 J / cm ² , but these conditions are not particularly limited.

  As a fifth step, an upper clad layer forming resin film is laminated on the lower clad layer 4 and the core portion 2 by the same method as the first and second steps. Here, the upper clad layer forming resin layer is designed to have a lower refractive index than the core portion forming resin layer. The thickness of the upper clad forming resin layer is preferably larger than the height of the core portion 2.

Next, the upper clad layer-forming resin layer is cured by light and / or heat to form the upper clad layer 3 in the same manner as in the first step.
The irradiation amount of the active light when the upper clad layer-forming resin layer is cured by light is not particularly limited, but is preferably 0.1 to 30 J / cm ² . Moreover, when actinic rays permeate | transmit a base material, in order to make it harden | cure efficiently, the double-sided exposure machine which can irradiate actinic rays simultaneously from both surfaces can be used. Moreover, you may irradiate actinic light, heating as needed, and you may heat-process as a process before and behind photocuring. The heating temperature during and / or after irradiation with actinic rays is not particularly limited, but is preferably 50 to 200 ° C.
The heating temperature when the upper clad layer forming resin layer is cured by heat is not particularly limited, but is preferably 50 to 200 ° C.
In addition, when the removal of the support film of the resin film for upper clad layer formation is required, it may remove before hardening or after hardening.
The optical waveguide 1 can be manufactured through the above steps.

  The following examples of the present invention will be described more specifically, but the present invention is not limited to these examples. Moreover, the weight average molecular weight and acid value of the obtained (meth) acrylic polymer were computed with the following method.

[Measurement of weight average molecular weight]
Measurement was performed using GPC (trade name: “SD-8022”, “DP-8020”, and “RI-8020” manufactured by Tosoh Corporation). In addition, the Hitachi Chemical Co., Ltd. product name: "Gelpack GL-A150-S" and "Gelpack GL-A160-S" were used for the column.
[Measurement of acid value]
It calculated from the amount of 0.1 mol / L potassium hydroxide aqueous solution required to neutralize the (meth) acrylic polymer solution. At this time, the point at which the phenolphthalein added as an indicator turned from colorless to pink was defined as the neutralization point.

Synthesis example 1
[Production of (Meth) acrylic polymer A-1]
46 parts by mass of propylene glycol monomethyl ether acetate and 23 parts by mass of methyl lactate were weighed in a flask equipped with a stirrer, a cooling pipe, a gas introduction pipe, a dropping funnel, and a thermometer, and stirred while introducing nitrogen gas. . The liquid temperature is raised to 65 ° C., 10 parts by mass of methacrylic acid, which is a raw material of the structural unit of formula (1), 65 parts by mass of benzyl methacrylate, which is a raw material of the structural unit of formula (2), 19 parts by mass of methyl methacrylate, 16 parts by mass of N-cyclohexylmaleimide, which is a raw material for the structural unit of (3), 2 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile), 46 parts by mass of propylene glycol monomethyl ether acetate and 23 parts by mass of methyl lactate After a portion of the mixture was added dropwise over 3 hours, the mixture was stirred at 65 ° C. for 3 hours, and further stirred at 95 ° C. for 1 hour to obtain a (meth) acrylic polymer A-1 solution (solid content: 45% by mass).
The obtained (meth) acrylic polymer A-1 had a weight average molecular weight of 3.6 × 10 ⁴ and an acid value of 61 mgKOH / g.

Synthesis example 2
[Production of (Meth) acrylic polymer A-2]
46 parts by mass of propylene glycol monomethyl ether acetate and 23 parts by mass of methyl lactate were weighed in a flask equipped with a stirrer, a cooling pipe, a gas introduction pipe, a dropping funnel, and a thermometer, and stirred while introducing nitrogen gas. . The liquid temperature is increased to 65 ° C., 14 parts by mass of methacrylic acid as a raw material for the structural unit of formula (1), 47 parts by mass of methyl methacrylate as a raw material for the structural unit of formula (2), 33 parts by mass of butyl acrylate, and A mixture of 16 parts by mass of 2-hydroxyethyl methacrylate, 3 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile), 46 parts by mass of propylene glycol monomethyl ether acetate and 23 parts by mass of methyl lactate was dropped over 3 hours. Thereafter, the mixture was stirred at 65 ° C. for 3 hours, and further stirred at 95 ° C. for 1 hour to obtain a (meth) acrylic polymer A-2 solution (solid content: 45 mass%).
The obtained (meth) acrylic polymer A-2 had a weight average molecular weight of 3.9 × 10 ⁴ and an acid value of 120 mgKOH / g.

Synthesis example 3
[Production of (Meth) acrylic polymer A-3]
46 parts by mass of propylene glycol monomethyl ether acetate and 23 parts by mass of methyl lactate were weighed in a flask equipped with a stirrer, a cooling pipe, a gas introduction pipe, a dropping funnel, and a thermometer, and stirred while introducing nitrogen gas. . The liquid temperature was raised to 65 ° C., 21 parts by mass of methacrylic acid as a raw material for the structural unit of formula (1), 55 parts by mass of benzyl methacrylate and 19 parts by mass of methyl methacrylate as the raw material for the structural unit of formula (2), 16 parts by mass of N-cyclohexylmaleimide, which is a raw material for the structural unit of (3), 2 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile), 46 parts by mass of propylene glycol monomethyl ether acetate and 23 parts by mass of methyl lactate After a portion of the mixture was added dropwise over 3 hours, the mixture was stirred at 65 ° C. for 3 hours, and further stirred at 95 ° C. for 1 hour to obtain a (meth) acrylic polymer A-3 solution (solid content: 45 mass%).
The obtained (meth) acrylic polymer A-3 had a weight average molecular weight of 3.5 × 10 ⁴ and an acid value of 120 mgKOH / g.

Example 1
[Preparation of resin varnish COV-1 for core formation]
As the component (A), 89 parts by mass (solid content: 45% by mass) of the above A-1 solution (solid content: 45% by mass), and as the component (B), urethane (meth) acrylate having a polyester skeleton (Shin Nakamura Chemical Industry ( Co., Ltd., trade name “U-108A”) 25 parts by mass, and as component (E), ethoxylated bisphenol A diacrylate (manufactured by Hitachi Chemical Co., Ltd., trade name “Fancryl FA-321A”) 20 parts by mass As component (C), bisphenol A type epoxy resin (manufactured by Japan Epoxy Resin Co., Ltd., trade name “Epicoat 1001” (epoxy equivalent 475 g / eq)) 15 parts by mass, as component (D), 1- [4- (2-Hydroxyethoxy) phenyl] -2-hydroxy-2-methyl-1-propan-1-one (Ciba Japan Co., Ltd., trade name “Irgacure 2”) 59 ") 1 part by mass, and 1 part by mass of bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide (manufactured by Ciba Japan Ltd., trade name" Irgacure 819 "), and propylene as an organic solvent for dilution 19 parts by mass of glycol monomethyl ether acetate was mixed with stirring. After pressure filtration using a polyflon filter having a pore size of 2 μm (trade name “PF020” manufactured by Advantech Toyo Co., Ltd.), degassing was performed under reduced pressure to obtain a resin varnish COV-1 for forming a core part.

[Preparation of Core Part Forming Resin Film COF-1]
The core part-forming resin varnish COV-1 is a PET film (manufactured by Toyobo Co., Ltd., trade name “Cosmo Shine A1517”, thickness 16 μm) of a support film (hereinafter also referred to as “core part support film”). On the non-treated surface, it was applied using a coating machine (trade name “Multicoater TM-MC” manufactured by Hirano Techseed Co., Ltd.), dried at 80 ° C. for 10 minutes and at 100 ° C. for 10 minutes, and then surface release treatment A PET film (manufactured by Teijin DuPont Films, trade name “Purex A31”, thickness 25 μm) is pasted as a protective film (hereinafter also referred to as “core protective film”), and a core part-forming resin film COF-1 is attached. Obtained. At this time, the thickness of the resin layer can be arbitrarily adjusted by adjusting the gap of the coating machine, but in this example, the thickness after curing is adjusted to be 50 μm in the core portion forming resin film. did.

Example 2
[Preparation of Clad Layer Forming Resin Varnish CLV-1]
As the component (A), 84 parts by mass (solid content: 45% by mass) of the A-2 solution (solid content: 45% by mass), and as the component (B), urethane (meth) acrylate having a polyester skeleton (Shin Nakamura Chemical Industry ( Co., Ltd., trade name “U-200AX”) 33 parts by mass, and urethane (meth) acrylate having a polypropylene glycol skeleton (made by Shin-Nakamura Chemical Co., Ltd., trade name “UA-4200”), 15 parts by mass ( C) As a component, hydrogenated bisphenol A type epoxy resin (manufactured by Japan Epoxy Resin Co., Ltd., trade name “Epicoat YX8034”, epoxy equivalent 290 g / eq) 15 parts by mass, (D) as component 1- [4- ( 2-hydroxyethoxy) phenyl] -2-hydroxy-2-methyl-1-propan-1-one (manufactured by Ciba Japan Co., Ltd., trade name “IRGA” 1959 parts by weight, 1 part by weight of bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide (manufactured by Ciba Japan Co., Ltd., trade name “Irgacure 819”), -0.2 part by mass of cyanoethyl-2-phenylimidazole (Shikoku Kasei Kogyo Co., Ltd., trade name “CUREZOL 2PZ-CN”) and 23 parts by mass of propylene glycol monomethyl ether acetate as an organic solvent for dilution were mixed. . After pressure filtration using a polyflon filter having a pore size of 2 μm (trade name “PF020” manufactured by Advantech Toyo Co., Ltd.), degassing was performed under reduced pressure to obtain a resin varnish CLV-1 for forming a cladding layer.

[Preparation of Clad Layer Forming Resin Film CLF-1]
The clad layer forming resin composition CLV-1 is a PET film (trade name “Cosmo Shine A4100” manufactured by Toyobo Co., Ltd., thickness 50 μm) of a support film (hereinafter also referred to as “clad layer support film”). It is coated on the non-treated surface using the above coating machine, dried at 100 ° C. for 20 minutes, and then subjected to surface release treatment PET film (manufactured by Teijin DuPont Films, trade name “Purex A31”, thickness 25 μm) Was pasted as a protective film (hereinafter also referred to as “clad layer protective film”) to obtain a resin film CLF-1 for forming a clad layer. At this time, the thickness of the resin layer can be arbitrarily adjusted by adjusting the gap of the coating machine. In this embodiment, the thickness after curing is 20 μm for the resin film for forming the lower cladding layer, and the upper cladding. In the resin film for layer formation, it adjusted so that it might be set to 60 micrometers.

Examples 3-6 and Comparative Examples 1-4
According to the blending ratio shown in Table 1, the core part-forming resin varnishes COV-2 to 6 and the clad layer-forming resin varnish CLV-2 to 4 were prepared, and the core part-forming resin film was prepared in the same manner as in Example 1. COF-2 to 6 and clad layer forming resin films CLF-2 to 4 were produced.

  The toughness of the core part-forming resin films COF-1 to 6 and the clad layer-forming resin films CLF-1 to CLF-4 thus obtained was evaluated by the following methods. The results are shown in Table 1.

[Toughness evaluation]
The core part-forming resin film was irradiated with 2000 mJ / cm ^{2 of} ultraviolet rays (wavelength 365 nm) using an ultraviolet exposure machine (MAP-1200-L manufactured by Dainippon Screen Co., Ltd.). After removing the support film and the protective film and curing at 160 ° C. for 1 hour, a cured film having a thickness of 50 μm was obtained.
The obtained cured film was cut into a width of 10 mm and a length of 70 mm, and a tensile test (RTM-100 made by Orientec Co., Ltd.) was used to conduct a tensile test (distance between grips: 50 mm) at a temperature of 25 ° C. and a tensile speed of 5 mm / It carried out based on JISK7127 on condition of min, and evaluated on the following references | standards.
◎: Tensile rupture elongation is 20% or more ◯: Tensile rupture elongation is 10% or more and less than 20% △: Tensile rupture elongation is 5% or more and less than 10% ×: Tensile rupture elongation is less than 5% The tensile elongation at break was calculated according to the following formula.
Tensile elongation at break (%) = (distance between grips at break (mm) −initial distance between grips (mm)) / initial distance between grips (mm) × 100

The symbols in Table 1 are as follows.
(A) Component * 1: Propylene glycol monomethyl ether acetate / methyl lactate solution of (meth) acrylic polymer A-1 prepared in Synthesis Example 1 (solid content 45% by mass)
* 2: Propylene glycol monomethyl ether acetate / methyl lactate solution of (meth) acrylic polymer A-2 produced in Synthesis Example 2 (solid content 45% by mass)
* 3: Propylene glycol monomethyl ether acetate / methyl lactate solution of (meth) acrylic polymer A-3 prepared in Synthesis Example 3 (solid content 45% by mass)
(B) Component * 4: Urethane (meth) acrylate having a polyester skeleton (manufactured by Kyoeisha Chemical Co., Ltd., trade name “NK Oligo U-108A”)
* 5: Urethane (meth) acrylate having a polyester skeleton (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name “U-200AX”)
* 6: Urethane (meth) acrylate having a polypropylene glycol skeleton (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name “UA-4200”)
* 7: Urethane (meth) acrylate having a carboxyl group and a polyether skeleton (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name “UA-6200”)
(E) Component * 8: Ethoxylated bisphenol A diacrylate (manufactured by Hitachi Chemical Co., Ltd., trade name “Fancryl FA-321A”)
* 9: Polypropylene glycol diacrylate, manufactured by Hitachi Chemical Co., Ltd., trade name “Fancryl FA-P270A”)
* 10: Ethoxylated bisphenol A diacrylate (manufactured by Hitachi Chemical Co., Ltd., trade name “Fancryl FA-324A”)
* 11: Dipentaerythritol hexaacrylate (manufactured by Kyoeisha Chemical Co., Ltd., trade name “Light Acrylate DPE-6A”)
(C) Component * 12: Bisphenol A type epoxy resin (manufactured by Japan Epoxy Resin Co., Ltd., trade name “Epicoat 1001”, epoxy equivalent 475 g / eq)
* 13: Hydrogenated bisphenol A type epoxy resin (manufactured by Japan Epoxy Resin Co., Ltd., trade name “Epicoat YX8034”, epoxy equivalent 290 g / eq)
* 14: Biphenyl / phenol novolac type epoxy resin (manufactured by Nippon Kayaku Co., Ltd., trade name “NC-3000”, epoxy equivalent 275 g / eq)
* 15: Fluorene bisphenol type epoxy resin (manufactured by Nagase ChemteX Corporation, trade name “ONCOAT EX-1020”, epoxy equivalent 305 g / eq)
(D) component * 16: 1- [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methyl-1-propan-1-one (manufactured by Ciba Japan, trade name “Irgacure 2959” ")
* 17: Bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide (Ciba Japan Co., Ltd., trade name “Irgacure 819”)
(F) component * 18: 1-cyanoethyl-2-phenylimidazole (manufactured by Shikoku Kasei Kogyo Co., Ltd., trade name “CURESOL 2PZ-CN”)
Organic solvent * 19: Propylene glycol monomethyl ether acetate

Example 7
[Fabrication of flexible optical waveguide]
Here, the optical waveguide 1 shown in FIG.
Using a roll laminator (manufactured by Hitachi Chemical Technoplant Co., Ltd., trade name “HLM-1500”), the lower clad layer forming resin film CLF-1 from which the clad layer protective film has been removed is treated with a surface release treatment PET film (Teijin). The product was laminated on DuPont Films Co., Ltd. (trade name “Purex A53”, thickness 50 μm) under the conditions of a pressure of 0.5 MPa, a temperature of 80 ° C., and a speed of 0.2 m / min. Furthermore, pressure bonding was performed using a vacuum pressure laminator (trade name “MVLP-500 / 600” manufactured by Meiki Seisakusho Co., Ltd.) under conditions of a pressure of 0.4 MPa, a temperature of 80 ° C., and a pressurization time of 30 seconds.
Next, using an ultraviolet exposure machine (Dainippon Screen Co., Ltd., trade name “MAP-1200-L”), the clad layer support film was removed after irradiation with ultraviolet rays (wavelength 365 nm) at 2000 mJ / cm ² . Then, the lower clad layer 4 was formed by heat-curing at 160 degreeC for 1 hour.

Subsequently, the core part-forming resin film COF-1 from which the core part protective film has been removed using the roll laminator is placed on the lower cladding layer 4 at a pressure of 0.5 MPa, a temperature of 80 ° C., and a speed of 0.2 m / min. It laminated | stacked on the conditions of. Further, the vacuum pressurizing laminator was used for pressure bonding under conditions of a pressure of 0.4 MPa, a temperature of 80 ° C., and a pressurization time of 30 seconds.
Subsequently, the core part 2 (core pattern) was exposed by irradiating 1000 mJ / cm < ² > of ultraviolet-rays (wavelength 365nm) with the said ultraviolet exposure machine through the negative photomask of 50 micrometers in width. After exposure and heating at 80 ° C. for 5 minutes, the core support film was removed and developed using propylene glycol monomethyl ether acetate / N, N-dimethylacetamide (mass ratio 70/30). Subsequently, after washing with propylene glycol monomethyl ether acetate, further washing with 2-propanol. Then, it was heated and dried at 80 ° C. for 30 minutes, then at 100 ° C. for 1 hour, and further heated and cured at 160 ° C. for 1 hour.

Next, the upper clad layer-forming resin film CLF-1 from which the clad layer protective film has been removed using the vacuum pressurizing laminator is placed on the core 2 and the lower clad layer 4 at a pressure of 0.4 MPa and a temperature of 100 ° C. And it laminated | stacked on the conditions of pressurization time 30 second. The upper clad layer 3 was formed by irradiating ultraviolet rays (wavelength 365 nm) at 2000 mJ / cm ² and removing the clad layer support film, followed by heat curing at 160 ° C. for 1 hour. Thereafter, the surface release-treated PET film was removed to obtain an optical waveguide 1 shown in FIG. Thereafter, a flexible optical waveguide having a length of 10 cm was produced using a dicing saw (trade name “DAD-522” manufactured by DISCO Corporation).

Examples 8 to 10 and Comparative Examples 5 and 6
A flexible optical waveguide was produced in the same manner as in Example 7 using the core portion forming resin films COF-2 to 6 and the cladding layer forming resin films CLF-1 to CLF-4.

  The measurement or test method of the light propagation loss measurement, the high-temperature and high-humidity storage test, the temperature cycle test, and the reflow test of the flexible optical waveguide (10 cm in length) thus obtained is as follows.

[Optical propagation loss measurement]
The optical propagation loss of the obtained flexible optical waveguide is a VCSEL (exfo company, product name “FLS-300-01-VCL”) having a light source of 850 nm wavelength as a light source and a light receiving sensor (manufactured by Advantest Co., Ltd.). , Trade name “Q82214”), an input fiber (GI-50 / 125 multimode fiber, NA = 0.20), and an output fiber (SI-114 / 125, NA = 0.22). The optical propagation loss was calculated by the optical loss measurement value (dB) / optical waveguide length (10 cm), and evaluated according to the following criteria.
◎: 0.1 dB / cm or less ○: Greater than 0.1 dB / cm, 0.2 dB / cm or less Δ: Greater than 0.2 dB / cm, 0.3 dB / cm or less ×: Greater than 0.3 dB / cm

[High temperature and high humidity test]
The obtained flexible optical waveguide was heated at a temperature of 85 under conditions in accordance with the JPCA standard (JPCA-PE02-05-01S) using a high-temperature and high-humidity tester (trade name “PL-2KT” manufactured by ESPEC Corporation). A high-temperature and high-humidity storage test at 1000 ° C. and a humidity of 85% was conducted for 1000 hours.
The light propagation loss of the optical waveguide after the high-temperature and high-humidity storage test was measured using the same light source, light receiving element, incident fiber, and output fiber as described above, and evaluated according to the following criteria.
◎: 0.1 dB / cm or less ○: Greater than 0.1 dB / cm, 0.2 dB / cm or less Δ: Greater than 0.2 dB / cm, 0.3 dB / cm or less ×: Greater than 0.3 dB / cm

[Temperature cycle test]
The obtained flexible optical waveguide was subjected to a temperature test using a temperature cycle testing machine (trade name “ETAC WINTECH NT1010” manufactured by Enomoto Kasei Co., Ltd.) under the conditions in accordance with the JPCA standard (JPCA-PE02-05-01S). A temperature cycle test between −55 ° C. and 125 ° C. was performed 1000 cycles. Detailed temperature cycle test conditions are shown in Table 2.

The light propagation loss of the optical waveguide after the temperature cycle test was measured using the same light source, light receiving element, incident fiber, and output fiber as described above, and evaluated according to the following criteria.
◎: 0.1 dB / cm or less ○: Greater than 0.1 dB / cm, 0.2 dB / cm or less Δ: Greater than 0.2 dB / cm, 0.3 dB / cm or less ×: Greater than 0.3 dB / cm

[Reflow test]
The obtained flexible optical waveguide was subjected to a reflow test machine (Furukawa Electric Co., Ltd., trade name “Salamanda XNA-645PC”) under the conditions according to “IPC / JEDEC J-STD-020B”. The reflow test at a temperature of 265 ° C. was performed three times under a nitrogen atmosphere. Detailed reflow conditions are shown in Table 3, and the temperature profile in the reflow furnace is shown in FIG.

The light propagation loss of the optical waveguide after the reflow test was measured using the same light source, light receiving element, incident fiber, and output fiber as described above, and evaluated according to the following criteria.
◎: 0.1 dB / cm or less ○: Greater than 0.1 dB / cm, 0.2 dB / cm or less Δ: Greater than 0.2 dB / cm, 0.3 dB / cm or less ×: Greater than 0.3 dB / cm

[Toughness evaluation]
The toughness was evaluated according to the following criteria by winding the obtained flexible optical waveguide around a rod having a radius of 1 mm.
○: No change ×: Crack generation or breakage

Table 4 shows the results of the light propagation loss measurement, the high temperature and high humidity standing test, the temperature cycle test, and the reflow test of the flexible optical waveguides obtained in Examples 7 to 10 and Comparative Examples 5 and 6.
The development conditions in Table 4 are shown in Table 5.

  From Tables 1 and 4, the resin composition for optical materials of the present invention is excellent in transparency, heat resistance, and toughness, and the optical waveguide produced using these has transparency, heat resistance, and environmental reliability. And it turns out that it is excellent in toughness. On the other hand, the resin composition for optical materials not belonging to the present invention shown in Comparative Examples 1 and 2 and the optical waveguide produced using these shown in Comparative Example 5 are excellent in transparency, heat resistance, and environmental reliability. Although it is, it turns out that it is inferior to toughness. Moreover, although the optical waveguide manufactured using the resin composition for optical materials not belonging to the present invention shown in Comparative Examples 3 and 4 and those shown in Comparative Example 6 are excellent in transparency and toughness, It turns out that it is inferior to heat resistance and environmental reliability.

  An optical waveguide using the resin composition for optical materials of the present invention is excellent in transparency, environmental reliability, heat resistance, and toughness. In addition, the optical material resin film using the optical material resin composition has a flatness of each layer, an interlayer adhesion between the clad and the core, and a resolution at the time of forming the optical waveguide core pattern (thin line) in the optical waveguide manufacturing process. (Narrow line correspondence) is further improved, flatness is excellent, and it is possible to form a fine pattern with a small line width and line spacing.

DESCRIPTION OF SYMBOLS 1 Optical waveguide 2 Core part 3 Upper clad layer 4 Lower clad layer 5 Base material

Claims (18)

  (A) Polymer having a carboxyl group, (B) Urethane (meth) acrylate, (C) Compound having two or more epoxy groups in the molecule, and (D) Radical polymerization initiator resin Composition. The resin composition for forming an optical waveguide according to claim 1, wherein the component (A) includes a (meth) acrylic polymer having a structural unit represented by the following general formulas (1) and (2).

(In the formula, R ¹ represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms, R ² represents a hydrogen atom or a methyl group, and X ¹ is a single bond or a divalent organic group having 1 to 20 carbon atoms. Indicates an organic group.)

(In the formula, R ³ represents a hydrogen atom or a methyl group, and R ⁴ represents a monovalent organic group having 1 to 20 carbon atoms.) The component (A) for forming an optical waveguide according to claim 2, comprising a (meth) acrylic polymer having a structural unit represented by the general formulas (1) and (2) and the following general formula (3). Resin composition.

(In the formula, R ⁵ represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms.)   The resin composition for optical waveguide formation in any one of Claims 1-3 in which (B) component contains the urethane (meth) acrylate which has a carboxyl group.   The optical waveguide according to claim 1, wherein the component (B) includes a compound having at least one selected from the group consisting of an alicyclic structure, an aromatic ring structure, and a heterocyclic structure in the molecule. Resin composition for forming.   The optical waveguide according to claim 1, wherein the component (C) contains a compound having at least one selected from the group consisting of an alicyclic structure, an aromatic ring structure, and a heterocyclic structure in the molecule. Resin composition for forming.   The resin composition for forming an optical waveguide according to any one of claims 1 to 6, wherein the epoxy equivalent of component (C) is 250 to 1,000 g / eq.   (D) The resin composition for optical waveguide formation in any one of Claims 1-7 in which a component contains radical photopolymerization initiator. For the total amount of components (A) to (C),
(A) The compounding quantity of a component is 10-85 mass%,
(B) The compounding quantity of a component is 10-85 mass%,
(C) The compounding quantity of a component is 1-40 mass%,
For 100 parts by mass of the total amount of components (A) to (C),
(D) The resin composition for optical waveguide formation in any one of Claims 1-8 whose compounding quantity of a component is 0.01-10 mass parts.   Furthermore, (E) The resin composition for optical waveguide formation in any one of Claims 1-9 containing the (meth) acrylate which does not have a urethane bond.   The resin composition for forming an optical waveguide according to claim 10, wherein the component (E) comprises a compound having at least one selected from the group consisting of an alicyclic structure, an aromatic ring structure, and a heterocyclic structure in the molecule. . For the total amount of components (A) to (C) and (E),
(A) The compounding quantity of a component is 10-85 mass%,
(B) 5-80 mass% of compounding quantities of a component,
(C) 1-40 mass% of compounding quantity of component,
(E) The compounding quantity of a component is 5-80 mass%,
For 100 parts by mass of the total amount of components (A) to (C) and (E),
(D) The resin composition for optical waveguide formation of Claim 10 or 11 whose compounding quantity of a component is 0.01-10 mass parts.   Furthermore, the resin composition for optical waveguide formation in any one of Claims 1-12 containing (F) hardening accelerator.   The resin for forming an optical waveguide according to claim 13, wherein the compounding amount of the component (F) is 0.01 to 10 parts by mass with respect to 100 parts by mass of the total amount of the components (A) to (C) and (E). Composition.   The resin film for optical waveguide formation using the resin composition for optical waveguide formation in any one of Claims 1-14.   The optical waveguide which has a core part and / or a clad layer using the resin composition for optical waveguide formation in any one of Claims 1-14.   An optical waveguide having a core portion and / or a clad layer using the resin film for forming an optical waveguide according to claim 15.   The optical waveguide according to claim 16 or 17, wherein a light propagation loss in a light source having a wavelength of 850 nm is 0.3 dB / cm or less.

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