JP2003121665A - Resin composition for optical waveguide and hardened product of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition for an optical waveguide which solves the problem by the solvent and has excellent processing property and to provide a hardened material of the composition. SOLUTION: The resin composition for an optical waveguide contains (A) a (meth)acrylate compound expressed by general formula (1) and (B) an ethylenic unsaturated group-containing compound except for the component (A). In formula (1), each of R1 and R2 represents a hydrogen atom or CH3 and the average of n ranges from 1 to 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition for an optical waveguide, which has excellent flatness and can be easily processed, which can be used in an optical circuit, and a cured product thereof.

[0002]

2. Description of the Related Art Quartz is often used as a material for optical waveguides, but it has a problem that it is difficult to fabricate a large area having a high processing temperature. Recently, research on plastic waveguides using polymethylmethacrylate, etc. has progressed from the viewpoint of ease of processing. Even when such a resin is used, the resin is applied to the substrate in a state of being dissolved in a solvent. After that, in order to remove the solvent to form the core portion and the like, the solvent must be removed at an appropriate rate when removing the solvent. When the removal rate is high, bubbles or voids are generated or internal strain is generated. If the removal rate is low,
It had the drawback of taking a long time. When the removal temperature is increased, bubbles or voids may be generated and internal strain may occur due to the difference in coefficient of thermal expansion between the resin and the substrate.
Further, when a soluble resin is used for the optical waveguide, it is necessary to prevent the resin portion already formed when the clad portion and the core portion are formed from melting. Therefore, it has been necessary to introduce a cross-linking component into the resin or change the resin components in the core and clad portions. Optical transmission loss factor in optical waveguide, high frequency of infrared vibration absorption, absorption loss such as ultraviolet absorption due to electronic transition, density
Scattering loss due to Rayleigh scattering due to concentration fluctuation can be cited, and external factors include absorption loss due to transition metals, OH groups, and other impurities, impurities such as dust and air bubbles, and core /
Scattering loss due to structural irregularities such as cladding interface irregularities, core diameter fluctuations, microbending, and orientation birefringence. Regarding Rayleigh scattering, the coexistence of regions having different refractive indices is not preferable, and those exhibiting a microphase-separated structure such as crystalline polymer, block copolymer, or graft copolymer in the optical waveguide are not preferable. Further, in order to suppress fluctuations in the solid due to thermal motion, a resin that is three-dimensionally cured by ultraviolet rays or the like is desired rather than a linear polymer. Also, peeling at the core / clad interface also causes transmission loss, so the clad resin has good adhesion to the core material,
Adhesiveness is required. Therefore, it is desired that the core part and the clad part have similar components. The refractive index of the core of the optical waveguide is required to be higher than that of the cladding. It is preferable that the cladding material of a general multimode waveguide has a refractive index difference of 2 to 3% or more of that of the core material. Further, in the case of optical waveguide in a single mode, when the cross section of the core part is a square having a side of 8 μm, a clad having a refractive index as small as 0.3% is required. The refractive index fluctuation of the material is 1000
A precision of 5 minutes is required. Therefore, the refractive index range (1.45 to 1.45) of silicon resin, polymethacrylate resin, polycarbonate resin, etc., which is often used for the clad material, is used.
1.60) that can control the core material (refractive index 1.46 to 1.
62) was desired.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide a resin composition for an optical waveguide which is excellent in processability and a cured product thereof.

[0004]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that a specific (meth) acrylate compound (A) and an ethylenically unsaturated group-containing compound (B) other than the component (A) are used.
The resin composition containing as a main component, the refractive index can be controlled to some extent by changing the composition, these resins have low viscosity before curing, excellent coating properties such as spin coating, and the core portion of the optical waveguide or It was found that when it is applied to a clad layer, it has excellent light transmittance and extremely excellent flatness, and has completed the present invention.

That is, the present invention provides (1) the (meth) acrylate compound (A) represented by the general formula (1).

[0006]

[Chemical 2]

(In the formula (1), R ₁ and R ₂ are each a hydrogen atom or CH ₃ , and the average value of n is a number of 1 to 5) and the ethylenic non-component other than the component (A). A resin composition for an optical waveguide containing a saturated group-containing compound (B), (2), a resin composition for an optical waveguide according to (1) containing a photopolymerization initiator (C), (3) ), (1) or a cured product of the resin composition for an optical waveguide according to (2).

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The resin composition for an optical waveguide of the present invention comprises an ethylenically unsaturated group-containing compound other than the (meth) acrylate compound (A) represented by the general formula (1) and the component (A). It is a mixture with (B).

In the present invention, the (meth) acrylate compound (A) represented by the general formula (1) is used. Specific examples of the (meth) acrylate compound (A) include O-phenylphenyloxyethyl (meth) acrylate, O-phenylphenyloxyethyloxyethyl (meth) acrylate and O-phenylphenyloxypropyl (meth) acrylate. Can be mentioned. It can also be obtained from the market. For example, manufactured by Nippon Kayaku Co.,
Product name KAYARAD OPP-1, KAYARADOP
P-2 etc. can be mentioned.

In the present invention, the ethylenically unsaturated group-containing compound (B) other than the component (A) is used. Specific examples of the component (B) include (meth) acrylate monomers, (meth) acrylate oligomers, maleimide compounds,
Examples thereof include vinyl ether compounds and N-vinyl compounds.

Specific examples of the (meth) acrylate monomers include dodecyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, isobornyl (meth) acrylate, adamantyl (meth) acrylate and tri-. Bromophenyl (meth) acrylate, methoxyphenyl (meth) acrylate, cyanophenyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate,
Polyethylene glycol mono (meth) acrylate, glycidyl (meth) acrylate, carbitol (meth)
Monofunctional (meth) acrylates such as acrylates. Diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, 1,4-butylene glycol di (Meth) acrylate, 1,5-pentanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexanediol polyethoxydi (meth) Acrylate, neopentyl glycol polypropoxydi (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (or tetra) (meth) acrylate neopentylglyce Di- (meth) acrylate of the ε-caprolactone adduct of trimethylol, tri (meth) acrylate of the ε-caprolactone adduct of trimethylolpropane, tri- or tetra (meth) acrylate of the ε-caprolactone adduct of pentaerythritol, dipenta Erythritol penta or hexa (meth) acrylate, poly (meth) adduct of dipentaerythritol with ε-caprolactone
Acrylate, ditrimethylolpropane tetra (meth) acrylate, tetrabromobisphenol A polyethoxydi (meth) acrylate, bisphenol A polyethoxydi (meth) acrylate, bisphenol hexafluoropropyl polyethoxydi (meth) acrylate, hydrogenated bisphenol hexafluoropropyl polyethoxydi Polyfunctionality (meth) such as (meth) acrylate
An acrylate etc. can be mentioned.

Specific examples of (meth) acrylate oligomers include polyester (meth) acrylate, urethane (meth) acrylate and epoxy (meth) acrylate.

Specific examples of polyester (meth) acrylates include (poly) ethylene glycol, (poly) propylene glycol, (poly) tetramethylene glycol, (poly) butylene glycol, neopentyl glycol, 1,6-hexanediol, 3-methyl-1,5
A polyol component such as pentanediol, cyclohexane-1,4-dimethanol, bisphenol A polyethoxydiol, hydrogenated bisphenol A, trimethylolpropane and maleic acid, succinic acid, fumaric acid, adipic acid, phthalic acid, isophthalic acid, Hexahydrophthalic acid,
Polymethacrylic acid such as tetrahydrophthalic acid, dimer acid, sebacic acid, azelaic acid, 5-sodium sulfoisophthalic acid and the like, and a (meth) acrylate of polyester polyol which is a reaction product thereof; Examples thereof include polyfunctional polyester (meth) acrylates such as (meth) acrylates of cyclic lactone-modified polyester polyols, which are reaction products of acids and their anhydrides with ε-caprolactone.

As a specific example of urethane (meth) acrylate, a reaction product of an organic isocyanate compound, a polyol compound and a hydroxyl group-containing (meth) acrylate compound can be mentioned as a typical example.

Specific examples of the organic polyisocyanate include P-phenylene diisocyanate, m-phenylene diisocyanate, P-xylene diisocyanate and m.
-Xylene diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,
Aromatic diisocyanates such as 4'-diphenylmethane diisocyanate and naphthalene diisocyanate; isophorone diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, 4,
Aliphatic or alicyclic diisocyanates such as 4'-dicyclohexylmethane diisocyanate, hydrogenated xylene diisocyanate, norbornene diisocyanate, and lysine diisocyanate; one or more burettes of isocyanate monomers, or trimers of the above diisocyanate compounds And the like.

Specific examples of the polyol compound include the above-mentioned polyol component, polyester polyol, cyclic lactone-modified polyester polyol and the like.

Specific examples of the hydroxyl group-containing (meth) acrylate compound include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate and cyclohexanedimethanol mono (meth). Acrylate, 4
-Hydroxybutyl (meth) acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, pentaerythritol tri (meth) acrylate, 2-hydroxy-
3-phenoxypropyl (meth) acrylate etc. can be mentioned.

Specific examples of the epoxy (meth) acrylate include a product obtained by reacting an epoxy resin having a bifunctional or higher epoxy group with (meth) acrylic acid.

Specific examples of the epoxy resin include bisphenol A diglycidyl ether and hydrogenated bisphenol A.
Diglycidyl ether, bisphenol hexafluoroacetone diglycidyl ether, tetrabromobisphenol A diglycidyl ether, 1,3-bis [1-
(2,3-epoxypropoxy) -1-trifluoromethyl-2,2,2-trifluoroethyl] benzene,
1,4-bis [1- (2,3-epoxypropoxy)-
1-trifluoromethyl-2,2,2-trifluoroethyl] benzene, 4,4'-bis (2,3-epoxypropoxy) octafluorobiphenyl, spiroglycol diglycidyl ether, polyethylene glycol diglycidyl ether, phenol Typical examples are novolac type epoxy resins, but the present invention is not limited thereto.

As specific examples of maleimide compounds, any compound containing a maleimide group can be used,
Examples thereof include a 1 to 3 functional maleimide compound described in JP-A-58-40374 and a maleimide group-containing urethane oligomer described in JP-A-3-12414.

Furthermore, as typical examples, N-methylmaleimide, N-ethylmaleimide, Nn-propylmaleimide, N-isopropylmaleimide, N-allylmaleimide, Nn-butylmaleimide, N-2. -Methyl-propylmaleimide, N-cyclohexylmaleimide, N-2-ethylhexylmaleimide, N- (2-
Dimethylaminoethyl) maleimide, N- (1-methoxymethylpropyl) maleimide, N, N'-1,6-hexane bismaleimide, bis (3-N-maleimidopropyl) polytetramethylene glycol, bis (2-N-
Maleimidopropyl) polypropylene glycol, bis (2-N-maleimidoethyl) polyethylene glycol, 1,2 (1,3 or 1,4) -bis (N-maleimidomethyl) cyclohexane,

[0022]

[Chemical 3]

[0023]

[Chemical 4]

[0024]

[Chemical 5]

And maleimide compounds in which hydrogen atoms bonded to unsaturated carbon atoms in maleimide groups of these maleimide compounds are substituted with chlorine atom, bromine atom, methyl group, ethyl group, methoxy group and the like. (In the chemical formula 4, a, b and c each independently represent a number of 0 to 3, and a + b + c represents a number of 1 to 5).

Specific examples of vinyl ether compounds include hydroxymethyl vinyl ether, chloromethyl vinyl ether, hydroxyethyl vinyl ether, 1,
4-butanediol divinyl ether, 1,6-hexanediol divinyl ether, 4-hydroxybutyl vinyl ether, trimethylolpropane trivinyl ether, cyclohexanedimethanol mono- or divinyl ether, cyclohexane mono- or divinyl ether, triethylene glycol divinyl ether, polytetra Examples thereof include methylene glycol divinyl ether, polyurethane polyvinyl ether, polyester polyvinyl ether and the like.

Specific examples of N-vinyl compounds include N
-Vinylpyrrolidone, N-vinylcaprolactam, N-
Examples thereof include vinylformamide and N-vinylacetamide.

Preferred examples of the ethylenically unsaturated group-containing compound (B) other than the component (A) include acrylate monomers, acrylate oligomers and maleimide compounds.

In the present invention, a photopolymerization initiator (C) is used as an optional component. Specific examples of the photopolymerization initiator (C) include 2,2-diethoxyacetophenone, 2,2-diethoxy-2-phenylacetophenone, benzophenone and 1- (4-isopropylphenyl) -2-hydroxy-2-methyl. Propan-1-one, 2-hydroxy-
2-methyl-1-phenylpropan-1-one, benzoin ethyl ether, benzoin isobutyl ether,
Examples thereof include benzoin isopropyl ether, 1-hydroxycyclohexyl phenyl ketone, methylbenzisoformate, and 2,4,6-trimethylbenzoyldiphenylphosphine oxide.

In the resin composition for an optical waveguide of the present invention, the ratio of the components (A) to (C) to be used is (A) component 1
The component (B) is preferably 10 to 500 parts by weight, particularly preferably 20 to 200 parts by weight, relative to 00 parts by weight, and the total amount of the components (A) + (B) is 100 parts by weight.
The component (C) is preferably 0 to 10 parts by weight, particularly preferably 0.05 to 6 parts by weight.

First, in the present invention, if necessary, a silane coupling agent, a titanium-based coupling agent, a flexibility imparting agent, a characteristic modifier, etc. can be added. The properties of the resin composition can be modified by adding these materials alone or in combination to the main component.

For example, as a silane coupling agent added to enhance the adhesiveness of the resin composition of the present invention, γ-
Aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β- (aminoethyl) -γ
-Aminopropyltrimethoxysilane, N-β- (aminoethyl) -γ-aminopropyltriethoxysilane,
N-β- (aminoethyl) -β- (aminoethyl) -γ
-Aminopropylmethyldimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, N-β- (N-vinyl Benzylaminoethyl) -γ-aminopropyltrimethoxysilane hydrochloride, methyltrimethoxysilane, methyltriethoxysilane, vinyltriacetoxysilane, γ-chloropropyltrimethoxysilane, hexamethyldisilazane, γ-
Anilinopropyltrimethoxysilane, vinyltrimethoxysilane, octadecyldimethyl [3- (trimethoxysilyl) propyl] ammonium chloride, γ-chloropropylmethyldimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, methyltrichlorosilane, vinyltriethoxy Silane, γ-methacryloxypropyltris (2-methoxyethoxy) silane, β-
(3,4-epoxycyclohexyl) ethyltrimethoxysilane and the like.

The resin composition of the present invention can be obtained by mixing and dissolving the components (A) to (C) and the above-mentioned coupling agent, etc., and filtering in a clean room.

As a method for producing the optical waveguide in the present invention, although the clad is slightly different when an ordinary polymer resin is used and when an ultraviolet curable resin similar to the core material is used,
As an example,

(1) A resin having a refractive index smaller than that of the core to be the lower clad is applied to an arbitrary substrate. After coating, the solvent is removed by heating and drying. When an ultraviolet curable resin is used here, it suffices that the resin is applied and then cured by ultraviolet rays. By using these cured resins, the step of removing the solvent can be omitted. (2) The resin of the present invention to be a core is applied onto this, and then, ultraviolet rays are applied through a negative mask having a waveguide pattern to cure the resin. After that, when this sample was developed with an organic solvent, only the light irradiation part was cured according to the mask pattern,
Waveguide patterns can be produced. (3) Thereafter, a polymer resin for clad or an ultraviolet curable resin is applied on this, and the solvent is removed or the resin is cured by ultraviolet rays. Here, it is desirable that the lower clad and the clad on the side surface of the core and the upper clad to be finally formed have the same refractive index, and the same material is more preferable. Furthermore, when an ultraviolet curable resin is used for the clad, the uppermost surface can be flattened. In this case, a multi-layered optical wiring becomes possible, and in case of multi-layering, the above (2) and (3) may be repeated.

[0036]

EXAMPLES The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. (Example) In the general formula (1), R ₁ = CH ₃ , R ₂ = H, n
O-phenylphenyloxyethyl acrylate with ≈1 (KAYARAD OPP-, manufactured by Nippon Kayaku Co., Ltd.)
1) 55.5 g, 5-ethyl-2- (2-hydroxy-
1,1-dimethylethyl) -5- (hydroxymethyl)
A resin composition (a) prepared from 44.5 g of -1,3-dioxane diacrylate (Nippon Kayaku Co., Ltd., KAYARAD R-604) and 3 g of 1-hydroxycyclohexyl phenyl ketone (photopolymerization initiator) was used. Got ready. The refractive index of the resin composition (a) after curing is 5
It was 1.550 at 89 nm.

Next, on the silicon substrate, the general formula (1)
Where R ₁ = CH ₃ , R ₂ = H, and n≈1 O-phenylphenyloxyethyl acrylate (Nippon Kayaku Co., Ltd.)
Manufactured by KAYARAD OPP-1) 26.9 g, 5-ethyl-2- (2-hydroxy-1,1-dimethylethyl) -5- (hydroxymethyl) -1,3-dioxane diacrylate (Nippon Kayaku KK, KAYARAD
The resin composition (b) prepared from 73.1 g of R-604) and 3 g of 1-hydroxycyclohexyl phenyl ketone was applied by spin coating, and the entire surface was irradiated with ultraviolet rays to form a 10 μm lower clad layer.

Next, the resin composition (a) was applied onto the lower clad layer by spin coating to a thickness of 5 μm. The refractive index of the lower clad layer after curing was 1.520 at a wavelength of 589 nm.

Next, ultraviolet rays were irradiated through a negative mask having a waveguide pattern, and then this sample was developed with γ-butyrolactone to prepare a waveguide pattern. Then, on this waveguide pattern and the lower clad layer,
The above resin composition (b) was applied to a thickness of 15 μm and irradiated with ultraviolet rays to be cured to prepare an optical waveguide. By this operation, a lower clad layer and an upper clad layer made of a cured product of the resin composition (b) having a refractive index of 1.520 after curing and a core made of a cured product of the resin composition (a) having a refractive index of 1.550 A multimode channel waveguide having the

The optical waveguide obtained was cut into a length of 5 cm, and the optical waveguide loss was examined by using a He-Ne laser beam having a wavelength of 633 nm. The loss was 0.30 dB / cm.

[0041]

As described above, according to the present invention, since the core material which does not use the solvent is used, the problem caused by the solvent is solved and the waveguide forming process is simplified. Further, since the flattening is easy, it is possible to realize an optical waveguide capable of multilayer optical wiring.

Claims (3)

[Claims] 1. A (meth) acrylate compound (A) represented by the general formula (1) and: (In the formula (1), R ₁ and R ₂ are each a hydrogen atom or CH ₃ , and the average value of n is a number of 1 to 5.) Containing an ethylenically unsaturated group other than the component (A) Compound (B)
A resin composition for an optical waveguide, comprising: 2. The resin composition for an optical waveguide according to claim 1, which contains a photopolymerization initiator (C). 3. A cured product of the resin composition for an optical waveguide according to claim 1.