KR100487025B1 - Photo-curable resin composition for optical waveguide and optical waveguide prepared therefrom - Google Patents

Abstract

The present invention provides (A) a fluorine-substituted photopolymerizable urethane oligomer represented by the following formula (1), (B) having (meth) acrylate (B ₁ ) having at least _one (meth) acryloyl group or at least one epoxy group A photocurable resin composition for an optical waveguide comprising a photoreactive monomer (B ₂ ), and (C) a photopolymerization initiator, wherein the composition exhibits low birefringence and low light loss, and has a light transmittance, thermal stability, and long-term storage properties. The optical waveguide can be produced easily and easily in mass production by the micro transfer molding technique using the resin composition:

Where

R ₁ is —CH ₂ O— or —CH ₂ (OCH ₂ CH ₂ ) _m O—, R ₂ is an aromatic or aliphatic hydrocarbon group of 6 to 100 carbon atoms, and R ₃ is of 2 to 10 carbon atoms It is an aromatic or aliphatic hydrocarbon group, R <_4> is a meta (acrylate) group or an epoxy group.

Description

Photo-curable resin composition for optical waveguide and optical waveguide manufactured therefrom {PHOTO-CURABLE RESIN COMPOSITION FOR OPTICAL WAVEGUIDE AND OPTICAL WAVEGUIDE PREPARED THEREFROM}

The present invention relates to a polymer for an optical waveguide device, and more particularly, to the preparation of a fluorine-substituted photocurable urethane oligomer having a photocurable (meth) acryl group or an epoxy group having a low light propagation loss, and a photocurable resin composition for an optical waveguide using the same. The present invention relates to a method for manufacturing a polymer optical waveguide by a micro molding technique using the composition.

The optical communication industry has become an indispensable medium for the transfer of countless amounts of information such as high definition and high definition video, electronic commerce, and video communication, which are needed in the information age that we will encounter in the future. Light is in the limelight because it is much faster than electrons and can deliver more information in a certain amount of time. Optical communication systems require multiple components such as multiplexing, demultiplexing devices, optical switches, optical amplifiers, photodetectors, and light sources, and various designs and materials have been improved to improve their performance.

First of all, from the material point of view, the optical waveguide including the optical switch is manufactured using silica. Since silica is the same material as the optical fiber, there is little reflection at the connection end when the optical fiber is connected and the light of the material itself is The loss is also very small, about 0.01 dB / cm. However, when the optical waveguide is manufactured using silica, a very high temperature energy is applied, and thus the thermal stress due to the difference in the thermal expansion coefficient of the silica during fabrication and cooling causes the polarization dependence of the material itself. The refractive index will also vary.

In order to improve this, research into organic polymer materials has been actively conducted. Compared to inorganic materials and semiconductors, organic polymer materials can be easily controlled / synthesized by molecular chemistry, economical due to low price, fast response speed, and very high bandwidths of tens to hundreds of Tbps. When manufacturing the device using the same can be carried out at a low temperature, the process is simple, the processability is good, and the integration is excellent. Despite these superior properties, organic polymeric materials have not been commercialized due to thermal instability and large optical transmission losses in the optical communication wavelength range.

In general, polymer materials used in planar waveguide optical devices and optical interconnections have thermal stability, low light loss in the optical communication wavelength region, fine refractive index control ability, low birefringence, adhesion to various substrates, Various lamination, dimensional stability and flexibility, easy alignment with fine optical parts, low cost, etc. conditions are required. In order to solve the problem of optical loss, researches on fluorine-substituted polymers are being actively conducted, and the substitution of deuterium or fluorine in the intramolecular CH bonds shifts the large infrared absorption wavelength in the wavelength range of 1.0 ~ 1.8㎛ to the long wavelength. It is possible to minimize the light absorption in the optical communication area.

NTT Co., Ltd. used a conventional polymer material for passive optical devices, or copolymerized deuterated methacrylate (MMA) and deuterated perfluoro methacrylate (MMA) monomers in various composition ratios to control the refractive index. By using the material as cladding and core, we realized a very low loss optical device with an excellent optical loss of 0.08 dB / cm at 1.3㎛. However, PMMA has a disadvantage in that its thermal stability is low as Tg is about 100 ° C. (S. Imamura et al., Electronics Letters , 27 , 1342, 1991). Perfluorinated polyimide, developed by NTT to overcome the low thermal stability of PMMA, has a problem in that polarization independence is difficult due to large birefringence and light loss due to relatively large hygroscopicity is generated. T. Matsuura et al., Electronics Letters , 29 (3), 269, 1993].

UV-curable fluorinated acrylate, announced by Allied Signal of the United States, uses thermal acrylate photo-crosslinking properties to secure thermal stability above 350 ° C. The optical losses at 1.3 μm and 1.55 μm were 0.03 dB / cm and 0.05 dB / cm, respectively, and continuous refractive index adjustment was possible from 1.3 to 1.6, and birefringence was polarized independent about 0.0008 [Elda (L. Eldada), et al., J. Lightwave Technology , 14 (7), 1704, 1996].

On the other hand, polyimide substituted by fluorine (CF) and diamine by chlorine (C-Cl) and fluorine and chlorine-substituted polymers, published by Samsung Electronics, have birefringence. Has great disadvantages [K. Han et al . , Polym. Bull. 41 , 455, 1998], a thermally crosslinked fluorine-substituted polyarylene ether, published by the Korea Electronics and Telecommunications Research Institute, is excellent in terms of thermal stability but low in productivity due to the thermosetting method [HJ Lee et al., J. Polym, Sci., Polym. Chem., 37 , 2355, 1999]. Korean Patent Application No. 1999-32681 discloses a fluorine-substituted polyimide having isotropic properties by introducing a fluorine-substituted aromatic group in the main chain of the polyimide into the outer chain, and recently, KJIST Cross-linkable Fluorinated Poly (arylene ether sulfide) crosslinked by curing has been developed and published (JW Kang et al., J. Lightwave Tech ., 19 (6), 872, 2001].

On the other hand, photolithography is widely used as a technique for manufacturing an optical waveguide, which is formed by spin coating a photoresist material on a core to form a pattern using a mask having a desired waveguide shape and inductive coupling. Dry etching the core material using a plasma. However, this method requires a lot of manufacturing time, and the etching is relatively easy when fabricating a single mode optical waveguide having a core size of about 4 to 8 μm, but when manufacturing a multimode optical waveguide, etching is performed at a depth of 40 μm or more. There is a problem to be done.

Accordingly, an object of the present invention is to provide a low-cost optical waveguide resin composition and a low birefringence, and a resin composition for the core layer and cladding layer having a low light progression loss, improved chemical resistance and thermal stability by photocuring It is to provide a method of manufacturing a device that is simple and easy to mass production by using a micro-transfer molding method.

In order to achieve the above object, the present invention provides a fluorine-substituted photopolymerized urethane oligomer (A) represented by the following formula (1), and also (A) fluorine-substituted photopolymerized urethane oligomer, (B) photoreactive monomer, Provided is a photocurable resin composition for an optical waveguide, comprising (C) a photopolymerization initiator, (D) an antioxidant, and (E) an antioxidant:

Formula 1

Where

R ₁ is —CH ₂ O— or —CH ₂ (OCH ₂ CH ₂ ) _m O—, R ₂ is an aromatic or aliphatic hydrocarbon group of 6 to 100 carbon atoms, and R ₃ is of 2 to 10 carbon atoms It is an aromatic or aliphatic hydrocarbon group, R <_4> is a meta (acrylate) group or an epoxy group.

The present invention also provides a polymer optical waveguide using the photocurable resin composition for the optical waveguide and a method of manufacturing the same.

Hereinafter, the present invention will be described in detail.

(A) Fluorine-substituted photopolymerized urethane oligomer

The photopolymerized urethane oligomer (A) used in the present invention is (a) polyol, (b) diisocyanate, (c) hydroxy (meth) acrylate or hydroxy epoxy (Hydroxy). Prepared by reacting Epoxy), (d) urethane reaction catalyst and (e) polymerization initiator.

(a) polyol

The polyol (a) used in the preparation of the fluorine-substituted photopolymerized urethane oligomer (A) has a molecular weight of preferably 500 to 10,000, and a fluorine-substituted perfluoropolyether polyol or a perfluoropolyether end Polyols having a non-fluorine polyether group are preferable. The polyol (a) is preferably used in an amount of 20 to 80% by weight of the composition for preparing a photopolymerizable urethane oligomer (A).

(b) diisocyanate

The diisocyanate (b) used in the preparation of the fluorine-substituted photopolymerized urethane oligomer (A) of the present invention is isophorone diisocyanate (IPDI), hexane diisocyanate (1,6-Hexane Diisocyanate, HDI), octa 1,8-Octamethylene Diisocyanate, Tetramethyl xylene diisocyanate (TMXDI), 4,4'-Dicyclohexylmethane diisocyanate (HMDI), 4, 4'-Diphenylmethane diisocyanate, 3,3'-dimethyl 4,4'-biphenylene diisocyanate (3,3'-Dimethyl-4,4'-biphenylene diisocyanate) , 3,3'-dimethyldiphenylmethane-4,4'-diisocyanate (3,3'-Dimethyldiphenylmethane-4,4'-diisocyanate), 4-bromo-6-methyl-1,3-phenylene di Isocyanate (4-Bromo-6-methyl-1,3-phenylene diisocyanate), 4-chloro-6-methyl-1,3-phenylene diisocyanate (4-Chloro-6-met hyl-1,3-phenylene diisocyanate), poly (1,4-butanediol) tolylene 2,4-diisocyanate terminated (Poly (1,4-butanediol) tolylene 2,4-diisocyanate terminated), poly (1 , 4-butanediol) isophorone diisocyanate terminated (Poly (1,4-butanediol) isophorone diisocyanate terminated), poly (ethylene adipate) tolylene 2,4-diisocyanate terminated (Poly (ethylene adipate) tolylene 2,4-diisocyanate terminated), poly [1,4-phenylene diisocyanate-co-poly (1,4-butanol)] diisocyanate (Poly [1,4-phenylene diisocyanate- co -poly (1,4- butanol)] diisocyanate), polyhexamethylene diisocyanate (Poly (hexamethylene diisocyanate), polypropylene glycol tolylene 2,4-diisocyanate terminated (Poly (propylene glycol) tolylene 2,4-diisocyanate terminated), poly (tetra Fluoroethylene oxide-co-difluoromethylene oxide) α, ω-diisocyanate (Poly (tetrafluoroeth ylene oxide-co-difluoromethylene oxide) α, ω-diisocyanate), 2,4-toluene diisocyanate, 2,5-toluene diisocyanate, 2,6 -2,6-Toluene Diisocyanate, 1,5-Naphthalene Diisocyanate, and mixtures thereof. The diisocyanate (b) is preferably used in an amount of 10 to 50% by weight of the composition for preparing the photopolymerized urethane oligomer (A).

(c) hydroxy (meth) acrylate or hydroxy epoxy

Component (c) used in the preparation of the photopolymerizable oligomer (A) of the present invention comprises a compound (c ₁ ) comprising at least one (meth) acryloyl group and a hydroxy functional group, or at least one epoxy group and a hydroxy functional group. Compound (c ₂ ).

Examples of the component (c ₁ ) include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-Hydroxypropyl (meth) acrylate, 2 2-Hydroxybutyl (meth) acrylate, 1-Hydroxybutyl (meth) acrylate (2-Hydroxybutyl (meth) acrylate), 2-hydroxy-3-phenyloxypropyl ( Meta) acrylate (2-Hydroxy-3-phenyloxypropyl (meth) acrylate), neopentylglycomono (meth) acrylate (Neopentylglycolmono (meth) acrylate), 4-hydroxycyclohexyl (meth) acrylate (4-Hydroxycyclohexyl (meth) acrylate, 1,6-hexanediol mono (meth) acrylate (1,6-hexanediolmono (meth) acrylate), pentaerythritolpenta (meth) acrylate (Pentaerythritolpenta (meth) acrylate), dipentaerytate Ditolentathritolpenta (meth) acrylate, 2-methacryloxyethyl 2-hydroxy propyl phthalate (2-Methacryloxyethyl 2-Hydr oxy Propyl Phthalate), Glycerin Dimethacrylate, 2-Hydroxy-3-acryloyloxy Propyl Methacrylate, Polycaprolactone Polyol Mono (meth) acrylates and mixtures thereof.

Examples of component (c ₂ ) include glycidol, epoxidized tetrahydrobenzyl alcohol, and the like.

The component (c) is preferably used in an amount of 5 to 50% by weight of the composition for preparing the photopolymerizable urethane oligomer (A).

(d) urethane reaction catalyst

The urethane reaction catalyst (d) used in the preparation of the photopolymerizable oligomer (A) of the present invention is a catalyst added in a small amount during the urethane reaction, and includes copper naphthenate, cobalt naphthenate, and zinc naphate ( zinc naphthate, n-butyltinlaurate, tristhylamine, 2-methyltriethlenediamide and mixtures thereof, and the photopolymerizable urethane oligomer (A) It is preferably used in an amount of 0.01 to 1% by weight of the composition for preparation.

(e) polymerization initiator

As a polymerization initiator (e) used in the preparation of the photopolymerizable oligomer (A) of the present invention, hydroquinone (Hydroquinone), hydroquinone monomethyl ether, Para-benzoquinone (Para-benzoquinone), phenothiazine and It is selected from the group consisting of a mixture thereof, and is preferably used in an amount of 0.01 to 1% by weight of the composition for preparing the photopolymerizable urethane oligomer (A).

Preparation of the fluorine-substituted photopolymerizable oligomer (A) may be carried out by a conventional method, and in particular, a fluorine-substituted perfluoro polyetherpolyol or a non-fluorine polyether at the perfluoropolyether terminal When the polyol having the group was added, the water was removed under reduced pressure, and half of the isocyanate and the total catalyst used were added thereto, and the temperature was maintained at 65 to 85 ° C. while stirring at 200 to 300 rpm, and the -OH peak disappeared on the IR. The reaction is carried out for about 2 to 3 hours. In this case, the amount of catalyst used may be used in the entire reaction. After completion of the reaction, a polymerization initiator and hydroxy (meth) acrylate or hydroxy epoxy were added, the temperature was raised to 70-90 ° C., the remaining amount of catalyst was added, and the reaction was carried out until the -NCO peak disappeared on IR, thereby fluorine substitution. A photopolymerization oligomer (A) can be manufactured.

The fluorine-substituted photopolymerized urethane oligomer (A) has an average molecular weight of 2,000 to 50,000, in addition to the excellent physical properties of the conventional urethane oligomer, the refractive index is low as about 1.3, 1.1 ~ 1.8㎛ wavelength region which is a characteristic that the optical waveguide material should have It has excellent light transmittance at the stage and is excellent in adhesiveness.

The fluorine-substituted photopolymerizable urethane oligomer (A) is preferably used in an amount of 20 to 80% by weight of the photocurable resin composition for an optical waveguide.

(B) reactive monomer

Examples of the reactive monomer (B) used in the present invention include a (meth) acrylate (B ₁ ) having at least _one (meth) acryloyl group or a photoreactive monomer (B ₂ ) having at least one epoxy group. (meth) acrylate (B ₁₎ comprises a fluorine-substituted monomer and bibul small monomer.

The reactive monomer (B) may be classified into a monomer having a (meth) acryloyl group or an epoxy group, a monofunctional monomer, a bifunctional monomer or a monomer having at least trifunctional groups.

Examples of the fluorine-substituted (meth) acryloyl group-containing reactive monomer include 2-perfluorooctylethyl acrylate, 2-perfluorooctylethyl methacrylate, and 2-perfluorooctylethyl methacrylate. , 2,3,4,4,4-hexafluorobutyl methacrylate (2,2,3,4,4,4-Hexafluorobutyl methacrylate), 2,2,3,3-tetrafluoropropyl methacrylate (2,2,3,3-Terrafluoropropyl methacrylate), Trifluoroethyl methacrylate, 2-Perfluoroalkylethyl acrylate, 2-perfluoroalkylethyl methacrylate Rate (2-Perfluoroalkylethyl methacrylate).

As monofunctional group non-fluorine-type reactive monomer containing one (meth) acryloyl group, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) Acrylate, 1-hydroxybutyl (meth) acrylate, 2-hydroxy-3-phenyloxypropyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, isodecyl ( Isodecyl (Meth) acrylate, 2- (2-ethoxyethoxy) ethyl (meth) acrylate (2- (2-Ethoxyethoxy) Ethyl (meth) acrylate), stearyl (meth) acrylate (Stearyl (Meth) acrylate), Lauryl (Meth) acrylate, 2-Phenoxyethyl (Meth) acrylate, Isobonyl (Meta) acrylate (Isobornyl (Meth) acrylate), Tridecyl (Meth) acrylate, Polycaprolactone (meth) acrylate Bit (Polycarprolactone (Meth) acrylate), and the like are phenoxy tetraethylene glycol acrylate (Phenoxy Tetraethylene Glycol (Meth) acrylate), imide acrylate (Imide acrylate).

Bifunctional non-fluorine monomers include ethoxylated nonyl phenol (meth) acrylate, ethylene glycol di (meth) acrylate, and diethylene glycol di (meth). Acrylate (Diethylene Glycol Di (meth) acrylate), triethylene glycol Di (meth) acrylate (Triethylene Glycol Di (meth) acrylate), tetraethylene glycol Di (meth) acrylate (Tetraethylene Glycol Di (meth) acrylate), Polyethylene Glycol Di (meth) acrylate, 1,6-hexanediol Di (meth) acrylate, 1,3-butylene glycol Di (meth) acrylate (1,3-Butylene Glycol Di (meth) acrylate), Tripropylene Glycol Di (meth) acrylate, Triethoxy Glycol Di (meth) acrylate, Ethoxy Immobilized Bisphenol A Di (meth) acrylic Ethoxylated Bisphenol A Di (meth) acrylate, Cyclohexane Dimeth It consists of a ethanol di (meth) acrylate (Cyclohexane Dimethanol Di (meth) acrylate), tricyclodecane dimethanol diacrylate (Tricyclo [5.2.1.0 ^2,6 ] decanedimethanol diacrylate).

Non-fluorine monomers having at least trifunctional groups include trisacryloyloxyethyl isocyanurate, trimethylol propane triacrylate, ethylene oxide 3 mole addition trimethylol propane triacryl Ethylene Oxide 6 Mole Addition Trimethylol Propane Triacrylate, Pentaerythritol Triacrylate, Tris (acryloxyethyl) isocyanurate, Dipentaerythritol Hexaacrylate and Caprolactone Modified Dipentaerythritol Hexa It is selected from the group consisting of acrylates.

Examples of the reactive monomer (B ₂ ) having one or more epoxy groups include 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexane carboxylate (3,4-Epoxycyclohexylmethyl-3,4-epoxy cyclohexane carboxylate), bis- ( Bis- (3,4-epoxycyclohexyl) adipate, 3-Ethyl-3-hydroxymethyl-oxetane, 1,2 Epoxyhexadecane (1,2-Epoxyhexadecane), alkyl glycidyl ether (Alkyl glycidyl ether), 2-ethylhexyl diglycol glycidyl ether (ethylene glycol diglycidyl ether) (Ethyleneglycol diglycidyl ether), Diethyleneglycol diglycidyl ether, PEG # 200 diglycidyl ether (PEG # 200 diglycidyl ether), PEG # 400 diglycidyl ether (PEG # 400 diglycidyl ether ), Propyleneglycol diglycidyl ether, Tripropyleneglycol diglycidyl ether ol diglycidyl ether, PPG # 400 diglycidyl ether, neopentylglycol diglycidyl ether, 1,6-hexanediol diglycidyl ether (1,6 -Hexanediol diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, propylene oxide modified bisphenol A diglycidyl ether of propyleneoxide modified bisphenol A, dibromo neopentyl glycol Diglycidyl ether (Dibromo neopentylglycol diglycidyl ether) and trimethylolpropane triglycidyl ether (Trimethylolpropane triglycidyl ether).

The photoreactive monomer (B) is preferably used in an amount of 20 to 80% by weight of the polymer resin composition for an optical waveguide.

(C) photopolymerization initiator

As the photopolymerization initiator (C) used in the present invention, Irgacure # 184, Irgacure # 907, Irgacure # 500, Irgacure # 651, Darocure # 1173, Darocure # 116, CGI # 1800, CGI # 1700, UVI-6990, UVI-6974 , Sarcat ^R CD1010, Sarcat ^R CD1011, Sarcat ^R CD1012, Sarcat ^R K185 and mixtures thereof, and is preferably used in an amount of 1 to 10% by weight of the polymer resin composition for an optical waveguide.

(D) polymerization inhibitor

In the composition of the present invention, the polymerization inhibitor (D) can be used to improve the storage stability, can prevent the curing phenomenon of the resin by free radicals that can be produced in a long-term storage or high temperature and high humidity environment, and the resin curing After the high temperature can prevent the yellowing phenomenon. The polymerization inhibitor is selected from the group consisting of hydroquinone, hydroquinone monomethylether, para-benzoquinone, phenothiazine, and mixtures thereof, and 0.01 of the polymer resin composition. To 5% by weight.

(E) antioxidant

Antioxidant (E) that can be used in the present invention is selected from the group consisting of Irganox 1010, Irganox 1035, Irganox 1076 (Cibageigy Co., Ltd.) and mixtures thereof, 0.01 to 5 weight of the polymer resin composition Can be used in amounts of%.

The photocurable resin composition for an optical waveguide of the present invention may be prepared by a conventional method, and specifically, the components (A) to (E) may be mixed in a reactor to have a humidity of 15 to 50 ° C. and 60% or less. It is preferably prepared by stirring at a speed of 500 to 1000 rpm. If the reaction temperature is less than 15 ℃, the viscosity of the oligomer (A) rises to cause a problem in the process, if it exceeds 50 ℃, the photopolymerization initiator (C) is not good because it forms a radical to cause a curing reaction. In addition, when the humidity exceeds 60% during the reaction, bubbles are generated in the resin during the coating process after the resin is generated, and unreacted substances react with moisture in the air, thereby causing side reactions.

The polymer resin composition for fluorine-substituted oligomer-containing optical waveguides according to the present invention can freely adjust the refractive index in the range of 1.38 to 1.54, and the viscosity closely related to workability can be easily controlled in the range of 50 to 2000 cPs, and long-term storage property Is also excellent. In addition, the thermal decomposition temperature is higher than 300 ℃ thermal stability, the birefringence is low as 1 × 10 ^-4 or less, by using a simple synthesis method can be manufactured at a low cost by reducing the manufacturing cost. In addition, it has excellent optical transmittance of 90% or more at wavelengths of 0.85 μm, 1.3 μm, and 1.55 μm, which are optical communication areas, and has an optical loss of about 0.3 dB / cm, particularly at 0.85 μm. The optical waveguide can be manufactured by a conventional thermosetting method, that is, a method of using a simple ultraviolet irradiation at room temperature instead of a method requiring a long time and a high temperature, thereby reducing the manufacturing process, cost, and time of the optical waveguide. You can.

The present invention also provides a method for producing a polymer optical waveguide, using a micro-transfer molding method. This method simplifies the manufacture of waveguides according to the conventional method which requires expensive equipment, difficult operating conditions, and the like, and uses a siloxane-based rubber to print out the pattern of the core.

As shown in Figure 1, the manufacturing process of the photocurable polymer optical waveguide using the micro transfer molding technique according to the present invention is as follows:

A siloxane-based resin, for example, polydimethyl siloxane rubber, is added to a substrate on which a waveguide pattern is formed by a photoresist and left at room temperature to remove air bubbles, followed by 2 to 10 at 30 to 100 ° C. After curing the resin for a period of time to remove from the master to prepare a cured siloxane-based mold. The polymer resin composition for photocurable fluorine-substituted optical waveguides of the present invention is coated on the siloxane mold by, for example, spin coating, and excess resin is removed at this time.

Meanwhile, on the under cladding layer coated and cured on a silicon wafer, the siloxane-based mold coated with the polymer resin of the present invention, prepared as described above, is covered with the polymer resin facing each other. After curing with ultraviolet light, the siloxane mold is removed therefrom. It is carried out by coating an upper cladding layer on the cured polymer resin and curing with ultraviolet rays. This micro transfer molding method has the advantage of being able to continuously manufacture a waveguide in a very simple process once a siloxane mold is manufactured, and can even form an optical waveguide having a size of 1 mm x 1 mm depending on the type of photoresist material. .

In the manufacturing process, a single-mode or multi-mode optical waveguide may be manufactured according to the design shape of the waveguide pattern.

The invention can be better understood by the following examples, which are intended for the purpose of illustration of the invention and are not intended to limit the scope of protection defined by the appended claims.

Example

Synthesis Example 1 Preparation of Oligomer

In a 1 L flask, 375.27 g of fluorosubstituted polyether (Fluorolink E10, manufactured by Ausimount, Italy) and 89.38 g of isophorone diisocyanate (IPDI) were mixed and warmed to 40 to 60 ° C, followed by n-butyltinlaurate (DBTL). ) 0.10 g was added. After the exotherm ended while stirring at 200 to 300 rpm, the reaction was continued until the -OH peak disappeared while maintaining the temperature at 65 to 85 ° C. When the -OH peak disappears completely on IR, 0.13 g of hydroquinone monomethyl ether (HQMME) and 34.85 g of 2-hydroxyethyl methacrylate (2-HEMA) are added, and when the exotherm ends, the temperature is increased to 70 to 90 ° C. The fluorine-substituted urethane oligomer was prepared by maintaining and reacting until the -NCO peak on the IR disappeared completely.

Synthesis Examples 2 to 13: Preparation of Oligomer

Using the components and contents shown in Table 1 below to prepare a fluorine-substituted urethane oligomer by the same method as in Synthesis Example 1.

Examples 1 to 10 and Comparative Example 1 Preparation of Polymer Resin for Optical Waveguide Production

The components shown in Table 2 were added to a reactor, and mixed at a temperature of 20 to 30 ° C., a humidity of 30 to 60%, and 300 to 1,000 rpm to prepare a fluorine-substituted polymer resin composition according to the present invention.

Example Comparative Example 1 One 2 3 4 5 6 7 8 9 10 (A) oligomer Synthesis Example 1 40 40 Synthesis Example 3 40 40 Synthesis Example 4 40 40 Synthesis Example 6 40 40 Synthesis Example 11 40 40 UVE-150 ^{(Note 1)} 40 (B) reactive monomer SR-339 ^{(Note 2)} 25 35 20 30 20 30 25 35 20 30 20 2-perfluorooctylethyl acrylate 25 15 20 20 20 20 25 15 20 20 10 2-hydroxypropylacrylate 10 10 10 20 (C) photoinitiator Darocure # 1173 ^{(Note 3)} 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 (D) polymerization inhibitor Z-6030 ^{(Note 4)} 5 5 5 5 5 5 5 5 5 5 5 (E) antioxidant BHT ^{(Note 5)} 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Sum 100 100 100 100 100 100 100 100 100 100 100

^{Note 1} : Croda product, ^{Note 2} : Sartomer company, ^{Note 3} : Ciba Geigy company

^{Note 4} : Dow Corning, ^{Note 5} : 2,6-di-tert-butyl-4-methylphenol (Aldrich-Chemical)

Property evaluation

The physical properties of the polymer compositions prepared in Examples 1-10 and Comparative Example 1, respectively, were evaluated by the following method, and the results are shown in Table 3 below.

1) Viscosity (cPs): Spinner No. 42 and a capacity of 2 ml were used as a Brookfield rotational viscometer at 25 ° C., and measured at 10 to 100 rpm according to the viscosity.

2) Refractive Index (Liquid): Measured by Sodium D line of 589.3 μm at 23 ° C. using an Abbe's Refractometer.

3) Refractive index (cured film): Place the silicon wafer on the vacuum chuck of the spin coater and evenly scatter the resin composition prepared in Example on it, and then 20 to 30 seconds at a speed of 1500 to 3000 rpm depending on the viscosity of the resin composition While coating. After coating is completed, it is cured at 100 mJ / ㎠ or more with a Fusion Lamp, an ultraviolet curing device made of 300W high-pressure mercury lamp, and after curing at 60 to 100 ° C for at least 10 minutes, a prism coupler (Prism) Coupler, Sairon Co. Ltd.) is used to measure the refractive index at 850 nm wavelength. When measuring the refractive index using a prism-coupler, the thickness of the film is suitably 2 to 15 µm.

The refractive index of the solid state is divided into nTE, which is the refractive index of the electric field mode, and nTM, which is the refractive index of the magnetic field mode, and the difference Δ (nTE-nTM) is an index indicating the birefringence of the coated material.

4) Light transmittance (% T): The polymer resin composition obtained in Example is coated on a glass plate with a thickness of 150 μm. After curing at 100 mJ / ㎠ or more with a fusion lamp of 300W high-pressure mercury lamp UV curing apparatus, the curing is carried out for 10 minutes or more at 60 ~ 100 ℃. After curing is complete, the specimens are separated to a size of 3 cm x 3 cm and the optical transmittance (% T) according to the wavelength of 200 to 1800 nm is measured with a spectrophotometer (UV-VIS-NIS Spectrophotometer, Varian, Australia). The light transmittance described in Table 2 below is the light transmittance in the 600 to 1600 nm wavelength region.

5) Hardness (A or D): The composition obtained in Example is carefully poured into a form having a size of 50 mm × 20 mm × 5 mm or more, and the curing conditions are the same as that of the sample curing at the time of measuring light transmittance. . After curing is completed, hardness is measured using a Shore Durometer Hardness.

6) Hardening Shrinkage (%): Measured according to ASTM D-792.

7) Glass Transition Temperature (Tg): The glass transition temperature was prepared using a Dynamic Mechanical Thermal Analyzer (DMTA) after preparing a cured film having a thickness of 150 μm in the same manner as the specimen manufacturing method for measuring the optical transmittance described above. Measure The measurement conditions were carried out in a nitrogen atmosphere from room temperature to 250 ° C. at a rate of temperature rise of 10 ° C./min.

8) Pyrolysis temperature (Td): Measure the change in the weight of the sample with increasing temperature under nitrogen atmosphere from room temperature to 700 ℃ at a temperature rising rate of 10 ℃ / min using a thermogravimeteric analyzer (TGA).

9) Storage Stability: After leaving the composition for 6 months at room temperature, observe the change in appearance and coating state before and after standing.

10) Light loss (dB / cm): The test piece for the optical loss measurement is the same as the test method for the test piece for the refractive index (solid) measurement. However, in order to measure the optical loss of a thin film using a refractive index matching method with a prism-coupler, a double layer film must be coated. That is, a material having a lower refractive index than the material to be measured is first coated on the silicon wafer, and then the composition to be measured is coated on the silicon wafer. In this test method, a total loss of 3 cm in length was taken, and a prism coupler was used as a prismatic coupler (Prism-Coupler) supplied by Sairon Co., Ltd.

Example 11 Fabrication of Optical Waveguides

The resin composition obtained in Example 1 was used as a cladding layer and evenly scattered on a silicon wafer, followed by spin coating at 3000 rpm for 30 seconds. Subsequently, curing was performed at 100 mJ / cm 2 or more with a fusion lamp, an ultraviolet curing device of 300W high-pressure mercury lamp, followed by post-curing at 60-100 ° C. for at least 10 minutes. On the other hand, polydimethylsiloxane rubber is added to a substrate on which a waveguide pattern is formed by a photoresist and left at room temperature to remove air bubbles, and then cured at 40 ° C. for 2 hours, and then removed from the master to form a cured siloxane-based mold ( Core size: 45 microns).

On the siloxane mold, the resin composition obtained in Example 2 was evenly added along the pattern shape while being careful not to bubble. The resin composition is placed on the cladding layer-coated silicon wafer with the resin composition facing downward, and then photocured at 100 mJ / cm 2 or more with a fusion lamp, and after removing the siloxane mold, at least 10 minutes at 60 to 100 ° C. And then cured. The cross section of the core layer coated wafer thus obtained was observed with an electron microscope and a scanning electron microscope, and the results are shown in FIGS. 2A and 2B, respectively.

The upper cladding layer was spin-coated at 1000 rpm for 20 seconds with the resin composition obtained in Example 1 while the core pattern was raised, and then photocured at 100 mJ / cm 2 or more, and then cured at 60 to 100 ° C. for 10 minutes or more. To obtain a polymer optical waveguide.

Example 12 Fabrication of Optical Waveguides

An optical waveguide was prepared in the same manner as in Example 11 except that the resin compositions obtained in Examples 3 and 4 were used as the cladding layer and the core layer, respectively.

Example 13: Measurement of physical properties of optical waveguide

The physical properties of the polymer optical waveguides obtained in Examples 11 and 12 are shown in Table 4 below, in which the propagation loss is 3 cm using a cut-back method at 850 nm. Measurement was made on the waveguide.

division Example 11 Example 12 Optical waveguide form Buried type Buried type Refractive index difference (%) 1.39% 1.40% Core size 45 μm × 45 μm 45 μm × 45 μm Optical running loss (dB / cm) 0.245 0.214

The resin composition for photocurable fluorine-substituted optical waveguides according to the present invention is a reactive monomer having at least one (meth) acryloyl group and an epoxy group together with a synthesized photocurable fluorine substituted oligomer having at least one (meth) acryloyl group. By mixing photopolymerization initiator, polymerization inhibitor and antioxidant, it shows low birefringence and low light loss, and is excellent in light transmittance, thermal stability and long-term storage, and also by micro-molding technique using the resin composition The optical waveguide can be easily manufactured by simply irradiating light without etching or etching.

Simple modifications or changes of the present invention can be easily carried out by those skilled in the art, and all such modifications or changes can be seen to be included in the scope of the present invention.

1 is a manufacturing process diagram of a photocurable polymer optical waveguide using a micro transfer molding technique according to an embodiment of the present invention;

2A and 2B are electron microscope and scanning electron microscope (Scanning Electron Microscope) photographs of the cross-sections of the core layer-coated wafers obtained in Examples of the present invention, respectively.

Claims (12)

A fluorine-substituted photopolymerized urethane oligomer represented by Formula 1 below: Formula 1 Where R ₂ is an aromatic or aliphatic hydrocarbon group having 6 to 100 carbon atoms, R ₃ is an aromatic or aliphatic hydrocarbon group having 2 to 10 carbon atoms, R ₄ is a meta (acrylate) group or an epoxy group, l and m Are each independently a positive integer and p is 0 or a positive integer. An optical waveguide comprising (A) 20 to 79% by weight of a fluorine-substituted photopolymerized urethane oligomer of Formula 1 according to claim 1, (B) 20 to 79% by weight of a reactive monomer and (C) 1 to 10% by weight of a photoinitiator. Photocurable resin composition. The method of claim 2, After the fluorine-substituted photopolymerized urethane oligomer (A) reacts the polyol (a) having a fluorine substituent and the diisocyanate (b) in the presence of a urethane reaction catalyst (d), the reaction product obtained and at least one (meth) acryl A compound (c) having a royl group or an epoxy group and a hydroxy group is prepared by reacting in the presence of a urethane reaction catalyst (d) and a polymerization initiator (e), wherein the photocurable resin composition for an optical waveguide. The method of claim 3, Photocurable resin for optical waveguides, characterized in that the polyol (a) has a molecular weight of 500 to 10,000, and a fluorine-substituted perfluoropolyether polyol or a polyol having a non-fluorine polyether group at the perfluoropolyether end. Composition. The method of claim 3, Diisocyanate (b) isophorone diisocyanate (IPDI), hexane diisocyanate (HDI), octamethylene diisocyanate, tetramethylxylene diisocyanate (TMXDI), 4,4'-dicyclohexylmethane diisocyanate (HMDI), 4,4'-diphenylmethane diisocyanate, 3,3'-dimethyl 4,4'-biphenylene diisocyanate, 3,3'-dimethyldiphenylmethane-4,4'-diisocyanate, 4-bromo -6-methyl-1,3-phenylene diisocyanate, 4-chloro-6-methyl-1,3-phenylene diisocyanate, poly (1,4-butanediol) tolylene 2,4-diisocyanate terminated , Poly (1,4-butanediol) isophorone diisocyanate terminated, poly (ethylene adipate) tolylene 2,4-diisocyanate terminated, poly [1,4-phenylene diisocyanate-co-poly ( 1,4-butanol)] diisocyanate, polyhexamethylene diisocyanate, polypropylene glycol toll Reylene 2,4-Diisocyanate Terminated, Poly (tetrafluoroethyleneoxide-co-difluoromethylene oxide) α, ω diisocyanate, 2,4-toluene diisocyanate, 2,5-toluene diisocyanate , 2,6-toluene diisocyanate, 1,5-naphthalene diisocyanate, and mixtures thereof. The photocurable resin composition for an optical waveguide. The method of claim 3, Compound (c ₁ ) having at least one (meth) acryloyl group and a hydroxy group is 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate , 1-hydroxybutyl (meth) acrylate, 2-hydroxy-3-phenyloxypropyl (meth) acrylate, neopentylglycomono (meth) acrylate, 4-hydroxycyclohexyl (meth) acrylate, 1,6-hexanediol mono (meth) acrylate, pentaerythritol penta (meth) acrylate, dipentaerythritol penta (meth) acrylate, 2-methacryloxyethyl 2-hydroxy propyl phthalate, glycerin di ( Optical waveguide, characterized in that it is selected from the group consisting of meth) acrylates, 2-hydroxy-3-acryloyloxy propyl (meth) acrylates, polycaprolactone polyol mono (meth) acrylates and mixtures thereof. Light Resin composition. The method of claim 3, Compound (c ₂ ) having at least one epoxy group and a hydroxy group is selected from the group consisting of glycidol, epoxidized tetrahydrobenzyl alcohol and mixtures thereof, the photocurable resin composition for an optical waveguide. The method of claim 2, The (meth) acrylate (B ₁ ) having at least one (meth) acryloyl group is a fluorine-substituted or unfluorinated monomer, and the fluorine-substituted (meth) acryloyl group-containing reactive monomer is 2-perfluoro Rooctylethyl acrylate, 2-perfluorooctylethyl methacrylate, 2,2,3,4,4,4-hexafluorobutyl methacrylate, 2,2,3,3-tetrafluoropropyl meta Acrylate, trifluoroethyl methacrylate, 2-perfluoroalkylethyl acrylate and 2-perfluoroalkylethyl methacrylate; The (meth) acryloyl group-containing reactive monomer which is not fluorine-substituted is 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 1- Hydroxybutyl (meth) acrylate, 2-hydroxy-3-phenyloxypropyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, isodecyl (meth) acrylate, 2- (2-ethoxy Ethoxy) ethyl (meth) acrylate, stearyl (meth) acrylate, lauryl (meth) acrylate, 2-phenoxyethyl (meth) acrylate, isobornyl (meth) acrylate, tridecyl (meth) Acrylate, polycaprolactone (meth) acrylate, phenoxytetraethylene glycol acrylate, imide acrylate, ethoxy-rich nonylphenol (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (Meta) Oh Relate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,3-butyl Ethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, ethoxy immobilized bisphenol A di (meth) acrylate, cyclohexane dimethanol di (meth) acrylate, tricyclodecane dimethanol diacryl Tricyclo [5.2.1.0 ^2,6 ] decanedimethanol diacrylate, tris acryloyloxyethyl isocyanurate, trimethylol propane triacrylate, ethylene oxide 3 molar addition trimethylol propane triacrylate, ethylene oxide 6 Molar addition type trimethylol propane triacrylate, pentaerythritol triacrylate, tris (acryloxyethyl) isocyanurate, dipenta Tall Tree hexaacrylate, caprolactone-modified dipentaerythritol hexa is selected from the group consisting of acrylate, which is characterized, photo-curing resin composition for the optical waveguide. The method of claim 2, Photoreactive monomer (B ₂ ) having at least one epoxy group is 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexane carboxylate, bis- (3,4-epcyclohexyl) adipate, 3-ethyl 3-hydroxymethyl-oxetane, 1,2-epoxyhexadecane, alkylglycidyl ether, 2-ethylhexyl diglycol glycidyl ether, ethylene glycol diglycidyl ether, diethylene glycol diglycidyl Ether, PEG # 200 diglycidyl ether, PEG # 400 diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, PPG # 400 diglycidyl ether, neopentylglycol di Glycidyl ether, 1,6-hexanediol diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, propylene oxide modified bisphenol A diglycidyl ether, dibromo neopentylglycol diglycidyl ether And trimethylolpropane triglycidyl ether Photocurable resin composition for an optical waveguide, characterized in that selected from the group consisting of. The method according to any one of claims 2 to 9, The birefringence is 1 × 10 ^-4 or less, the refractive index can be adjusted in the range of 1.38 to 1.54, the viscosity can be adjusted in the range of 50 to 2000 cps, the thermal decomposition temperature is characterized in that 300 ℃ or more, optical waveguide sight Chemical composition. 10. After applying the photocurable resin composition of any one of claims 2 to 9 to the siloxane-based mold and removing excess photocurable resin, the photocurable silicon wafer coated with the lower cladding layer is coated with the photocurable resin. Attaching a siloxane mold to the lower cladding coating surface and photocuring to remove the siloxane mold, and coating and photocuring the upper cladding layer on the photocurable resin. An optical waveguide manufactured according to the method of claim 11.