JP2007070327A - Oxetane ether compound having carboxyl group, method for producing the same and optical waveguide using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new oxetane ether compound having carboxyl group, capable of producing a polymer excellent in thick membrane-forming property, curing property, heat resistance, etc., a method for producing the same and an optical waveguide using the same. <P>SOLUTION: The compounds are e.g. 3,5-bis(3-ethyloxetanyl-3-methoxy)benzoic acid, 5-(3-ethyloxetanyl-3-methoxy)isophthalic acid, etc., and they are produced by etherizing 3,5-dihydroxybenzoic acid or dimethyl 5-hydroxyisophthalate by 2-(3-oxetanyl)butyltosylate and then hydrolyzing its ester group. Further, an optical wave guide comprising a substrate plate 1 and a cladding layer 2 formed on the substrate plate 1, and formed with a core part 3 having a prescribed pattern and transmitting light signals, in the cladding layer 2 is provided with that at least one of the cladding layer 2 and core part 3 is formed by a resin composition containing the above compounds. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an oxetane ether compound having an oxetane ring capable of cationic polymerization, a method for producing the same, and an optical waveguide using the same. Specifically, a photo-curing resin and a thermosetting resin using the compound are excellent in heat resistance, mechanical properties, low water absorption, coating film flatness, adhesion, etc. It relates to the optical waveguide used.

  Oxetane compounds are recently attracting attention as monomers capable of photoinitiated cationic polymerization or curing, and many monofunctional and polyfunctional oxetane compounds have been developed, and accordingly, methods for synthesizing various oxetane compounds. Has been proposed.

  As said oxetane compound, the oxetane compound represented by following General formula (6) is proposed also in the patent document, for example (refer patent document 1).

  Furthermore, biphenyl derivatives having an oxetane ring represented by the following general formula (7) and general formula (8) have also been proposed (see Patent Documents 2 and 3).

The above compounds are usually obtained by synthesizing an oxetane sulfonic acid ester and a corresponding dihydric phenol compound in the presence of an alkali metal such as sodium hydroxide or potassium hydroxide as a base. can get. In the synthesis, a phase transfer catalyst such as a quaternary ammonium salt is also used as necessary to increase the yield of the compound. Furthermore, the oxetane compound has been conventionally used for materials such as paints and adhesives in order to improve heat resistance, adhesion, etc. In recent years, it has also been proposed to use it as a material for forming optical waveguides. (See Patent Documents 4 and 5). Optical waveguides are incorporated in optical waveguide devices, optical integrated circuits, and optical wiring boards, and are widely used in the fields of optical communication, optical information processing, and other general optics.
JP-A-6-16804 JP-A-11-106380 JP 2001-31665 A JP 2000-356720 A JP 2003-147045 A

  However, among the oxetane compounds, the biphenyl derivative is a compound having a low molecular weight, and thus has a low viscosity. For example, when a film is formed on a substrate, it has a difficulty in forming a thick film. Moreover, since it is bifunctional, there also exists a fault that hardening requires time. Further, other oxetane compounds have a problem that it is difficult to obtain desired thick film formability and curability.

  In addition, when such a conventional oxetane compound is used, for example, as a material for forming an optical waveguide, it is difficult to stably cure and produce the same shape. There are also problems such as inability to form.

  Furthermore, the conventional method for synthesizing an oxetane compound also has a problem that the introduction of an oxetanyl group does not proceed quantitatively and the yield of the target oxetane compound is low. In addition, since a compound having an unreacted hydroxyl group is generated as a by-product, a complicated operation is often involved before obtaining the target oxetane compound.

  The present invention has been made in view of such circumstances, and a novel oxetane ether compound having a carboxyl group that makes it possible to produce a polymer excellent in thick film formability, curability, heat resistance, and the like, and a method for producing the same, and An object is to provide an optical waveguide using the same.

  In order to achieve the above object, the first gist of the present invention is an oxetane ether compound having a carboxyl group represented by the following general formula (1) or general formula (2).

  The present invention also provides a process for producing an oxetane ether compound having a carboxyl group as defined in the first aspect, wherein a phenol represented by the following general formula (3) or general formula (4) is converted to cesium by a cesium salt. The second gist is a method for producing an oxetane ether compound having a carboxyl group which is converted to phenolate and then reacted with a sulfonic acid ester represented by the following general formula (5).

  Furthermore, the present invention is an optical waveguide comprising a substrate and a clad layer formed on the substrate, wherein a core portion that propagates an optical signal in a predetermined pattern is formed in the clad layer, An optical waveguide in which at least one of the cladding layer and the core part is formed of the resin composition containing the oxetane ether compound having a carboxyl group of the first aspect is a third aspect.

  That is, the present inventors have developed an oxetane compound that is excellent in heat resistance, mechanical properties, etc., and can produce a polymer that can be effectively used as a material for paints, coating materials, adhesives, lenses, optical waveguides, and the like. We sought and intensively studied. And as a result of synthesizing various compounds having a special structure and repeating experiments, when an oxetane ether compound having a novel carboxyl group represented by the general formula (1) or the general formula (2) is used, As a result, the present invention has been achieved. That is, since the above-mentioned novel compound has one or two oxetane rings in one molecule, it has fast curability and the cured product forms a high-density network structure. It will have. In addition, the above-mentioned new compound is not a low molecular weight but a high molecular weight like existing compounds, so it has a high viscosity and is advantageous when forming a thick film, especially for the formation of optical waveguides (cladding layer and core part). When used as a material, it is easy to cure and produce the same shape in a stable manner, so that effects such as stabilization of waveguide characteristics can be obtained. On the other hand, the present inventors have also conducted research on a synthesis method capable of synthesizing the novel compound with high yield. As a result, the phenol represented by the general formula (3) or the general formula (4) and the sulfonic acid ester of 3-alkyl-3-hydroxymethyloxetane represented by the general formula (5), As a result, it was also found that the target novel compound can be synthesized in a high yield as a result of the reaction under a predetermined condition using a cesium salt as a base.

  As described above, the present invention relates to an oxetane ether compound having a novel carboxyl group represented by the general formula (1) or the general formula (2). Since this compound has a high molecular weight rather than a low molecular weight like existing compounds, it has a high viscosity and can easily form a thick film. Moreover, since it contains one or two oxetane rings in one molecule, it has the property of being rapidly cured by light or heat. Therefore, the photocurable resin composition and the thermosetting resin composition using the oxetane ether compound having a carboxyl group of the present invention are excellent in curability, heat resistance, toughness and mechanical properties, and have a low water absorption and a coating film. The flatness and adhesion are high, and the use of a polymerization initiator can be reduced due to its high reactivity, so the transparency is also high. For example, paints, coating materials, adhesives, optical lenses, optical waveguides, etc. It is useful as a forming material.

  And when synthesizing the oxetane ether compound having the carboxyl group, a specific oxetane sulfonic acid ester and a specific phenol are reacted with each other under a predetermined condition using a cesium salt as a base. It can be synthesized in high yield without complicated operations.

  Furthermore, when at least one of the cladding layer and the core portion in the optical waveguide is formed of a resin composition containing an oxetane ether compound having a carboxyl group represented by the general formula (1) or the general formula (2). Therefore, it is easy to stably produce the same shape, and stable waveguide characteristics can be obtained.

  Next, an embodiment of the present invention will be described.

The oxetane ether compound having a carboxyl group of the present invention is a compound represented by the following general formula (1) or general formula (2), and has a structure having one or two oxetane rings in one molecule. ing. In general formula (1) and general formula (2), examples of the alkyl group having 1 to 6 carbon atoms represented by R ₁ include a methyl group, an ethyl group, a propyl group, and a butyl group. Preferably, they are a methyl group and an ethyl group. In the general formula (1) and general formula (2), examples of the aliphatic chain organic group having 1 to 6 carbon atoms represented by R ₂ and R ₃ include a methyl group, an ethyl group, a propyl group, Examples thereof include an isopropyl group and a butyl group, and a methyl group is preferable.

  The oxetane ether compound having a carboxyl group represented by the general formula (1) or the general formula (2) includes a phenol represented by the following general formula (3) or the general formula (4), and the following general formula: It can be produced by reacting a sulfonic acid ester of 3-alkyl-3-hydroxymethyloxetane represented by (5) with a base as a synthesis raw material.

  Here, as the base, a conventionally known alkali metal (sodium hydroxide, potassium hydroxide, etc.) may be used. However, in the present invention, particularly when a cesium salt is used as the base, the carboxyl group is used. Since the oxetane ether compound having a high yield can be synthesized without complicated operations, it is preferable. In this case, for example, synthesis of each raw material is performed by, for example, (i) converting phenols to cesium phenolate with a cesium salt and then reacting with oxetane sulfonate, or (ii) oxetane sulfonate and phenol. The reaction is carried out in the presence of a cesium salt. Preferably, it is carried out according to the procedure (i) above. The above synthesis is usually carried out in an organic solvent (reaction solvent), and after the reaction is completed, water or the like is added to the reaction solution to form an aqueous phase and an organic phase, and extraction from the organic phase is performed for the purpose. An oxetane ether compound having a carboxyl group can be obtained.

  Examples of the cesium salt include cesium carbonate, cesium hydroxide, cesium fluoride, cesium formate, and the like. Among these, cesium carbonate is preferably used because the target oxetane ether compound having a carboxyl group can be obtained in a higher yield.

  And the usage-amount of the said cesium salt can be set to 0.8-2.0 mol with respect to 1 mol of phenolic hydroxyl groups of the phenol represented by the said General formula (3) or General formula (4). Preferably, it is in the range of 1.0 to 1.5 mol.

  Specific examples of the phenols represented by the general formula (3) are not particularly limited. For example, dimethyl 5-hydroxyisophthalate, dimethyl 4-hydroxyisophthalate, dimethyl 2-hydroxyisophthalate, 2 -Dimethyl hydroxyterephthalate and the like. These may be used alone or in combination of two or more. In addition, specific examples of the phenols represented by the general formula (4) are not particularly limited. For example, methyl 3,5-dihydroxybenzoate, methyl 2,4-dihydroxybenzoate, 2, Examples include methyl 5-dihydroxybenzoate and methyl 2,6-dihydroxybenzoate. These may be used alone or in combination of two or more.

  A specific example of the sulfonic acid ester of 3-alkyl-3-hydroxymethyloxetane represented by the general formula (5) used together with the above phenols is 2- (3-oxetanyl) propylmesi Rate, 2- (3-oxetanyl) propylphenylsulfonylate, 2- (3-oxetanyl) propyl tosylate, 2- (3-oxetanyl) butyl mesylate, 2- (3-oxetanyl) butyl tosylate and the like It is done. These may be used alone or in combination of two or more.

  The sulfonic acid ester of 3-alkyl-3-hydroxymethyloxetane represented by the general formula (5) is, for example, organic synthesis vol. 1 [Organic Synthesis, Collective vol. 1, pp. 145 (1941)]. It can be synthesized according to the method described in 1.

  Furthermore, the use amount of the sulfonic acid ester of 3-alkyl-3-hydroxymethyloxetane represented by the general formula (5) is the phenolic hydroxyl group of the phenol represented by the general formula (3) or (4). The amount is preferably set to 1.5 to 2.0 mol, more preferably 1.0 to 1.5 mol with respect to 1 mol.

  And at the time of manufacture of the oxetane ether compound which has a carboxyl group of this invention, it is preferable to set the reaction temperature in the case of the synthesis | combination to 0-120 degreeC, More preferably, it is the range of 60-100 degreeC. Moreover, when phenols are cesium phenolated in advance with a cesium salt, the reaction temperature in the cesium phenolate is preferably set to 0 to 120 ° C, more preferably in the range of 40 to 100 ° C. . And the pressure in these reactions is not specifically limited, Any of a normal pressure, pressurization, and pressure reduction may be sufficient. Also, the reaction atmosphere is not particularly limited.

  In addition, when synthesizing the oxetane ether compound having a carboxyl group of the present invention, an alkali metal such as sodium or potassium, an alkali metal hydride such as lithium hydride or sodium hydride, sodium hydroxide, An alkali metal hydroxide such as potassium oxide, an alkali metal carbonate such as sodium carbonate, or the like may be appropriately added as a synthetic raw material.

  Moreover, you may add a quaternary ammonium salt, a quaternary phosphonium salt, etc. as a phase transfer catalyst between an aqueous phase and an organic phase as needed. The quaternary ammonium salt is not particularly limited, and examples thereof include tetraalkylammonium halides such as tetrabutylammonium bromide (TBAB) and tetraethylammonium bromide, and aralkyltrialkylammonium halides such as benzyltrimethylammonium chloride. Can be given. The quaternary phosphonium salt is not particularly limited, and examples thereof include tetraarylphosphonium halides such as tetraphenylphosphonium bromide.

  Furthermore, when producing the oxetane ether compound having a carboxyl group of the present invention, a reaction solvent is usually used as described above. The reaction solvent is not particularly limited. For example, aromatic hydrocarbons (toluene, xylene, etc.), ethers (tetrahydrofuran, dibutyl ether, etc.), aprotic polar solvents (N-methylpyrrolidone, N-methyl-2- Pyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, etc.) are preferably used. These may be used alone or in combination of two or more.

  As described above, the oxetane ether compound having a carboxyl group synthesized by each of these raw materials is usually separated into an aqueous phase and an organic phase by adding water or ethyl acetate to the reaction solution. What extracted the organic phase can be collect | recovered by drying with anhydrous magnesium sulfate etc.

  The oxetane ether compound having a carboxyl group of the present invention thus obtained is effective as a material for a photocurable resin and a thermosetting resin constituting a paint, a coating material, an adhesive, a lens, an optical waveguide, and the like. Can be used.

  Among them, an optical waveguide, specifically, as shown in FIG. 1, includes a substrate 1 and a cladding layer 2 formed on the substrate 1, and propagates an optical signal in a predetermined pattern in the cladding layer 2. In the optical waveguide in which the core portion 3 is formed, when at least one of the cladding layer 2 and the core portion 3 is formed of a resin composition containing an oxetane ether compound having a carboxyl group, the compound has a high molecular weight. Therefore, the viscosity becomes high, which is advantageous when forming a thick film. In addition, it is possible to obtain an effect such as that the waveguide characteristics can be stably stabilized by being easily cured in the same shape. The clad layer 2 needs to have a refractive index smaller than that of the core portion 3.

  Further, when at least one of the clad layer 2 and the core part 3 is formed of a resin composition containing an oxetane ether compound having a carboxyl group and a compound having an epoxy group or a vinyl ether group according to the present invention, This is preferable because a cured product excellent in heat resistance and moisture resistance can be obtained and the exposure sensitivity can be improved. Here, as the compound having an epoxy group, any compound that is compatible with the compound represented by the formula (1) or the formula (2) of the present invention can be used. Specifically, examples of the epoxy compound having one epoxy group include phenyl glycidyl ether and butyl glycidyl ether, and examples of the epoxy compound having two or more epoxy groups include bisphenol A diglycidyl ether and bisphenoxyethanol full orange. Glycidyl ether, trimethylolpropane triglycidyl ether, bisphenolfluorene tetraglycidyl ether, 3,4-epoxycyclohexenylmethyl-3 ', 4'-epoxycyclohexene carboxylate, 2,2-bis as a compound having an alicyclic epoxy group An adduct of 1,2-epoxy-4- (2-oxiranyl) cyclohexane with (hydroxymethyl) -1-butanol is preferably used. Moreover, as a compound which has the said vinyl ether group, as long as it shows compatibility with the compound represented by Formula (1) or Formula (2) of this invention, all can be used. Specifically, examples of the compound having one vinyl ether group include hydroxyethyl vinyl ether, hydroxybutyl vinyl ether, dodecyl vinyl ether and the like. As the compound having two or more vinyl ether groups, cyclohexane dimethanol divinyl ether, triethylene glycol divinyl ether, novolak type divinyl ether and the like are preferably used. And these compounds are used individually or in combination of 2 or more types.

  And the said optical waveguide can be manufactured by a process as shown in FIG. 2, for example. That is, as shown in FIG. 2A, first, a substrate 1 is prepared, and as shown in FIG. 2B, an under cladding layer 2a (a lower portion of the cladding layer 2) is formed on the surface of the substrate 1. Next, as shown in (c), a layer 3 ′ made of a resin composition for forming the core portion 3 is formed on the under cladding layer 2 a. Then, as shown in (d), a photomask 9 for exposing a predetermined pattern (optical waveguide pattern) is disposed on the surface of the resin composition layer 3 ′, and ultraviolet rays are emitted through the photomask 9. Irradiation and further heat treatment. Thereafter, the unexposed portion of the resin composition layer 3 ′ is dissolved and removed using a developer to form the core portion 3 as shown in FIG. Then, as shown in (f), the over clad layer 2b (the upper portion of the clad layer 2) is formed on the core portion 3. Thereby, the target optical waveguide can be obtained.

  Each layer on the substrate 1 can be formed by a conventionally known method such as spin coating or coater. The optical waveguide can also be made into a film-like optical waveguide by peeling and removing the substrate 1. In such a configuration, the flexibility becomes excellent.

  The optical waveguide thus obtained is, for example, a straight optical waveguide, a curved optical waveguide, a crossed optical waveguide, a Y-branch optical waveguide, a slab optical waveguide, a Mach-Zehnder optical waveguide, an AWG optical waveguide, a grating, or an optical waveguide lens. Etc. can be used. Optical devices using these optical waveguides include wavelength filters, optical switches, optical splitters, optical multiplexers, optical multiplexers / demultiplexers, optical amplifiers, wavelength converters, wavelength dividers, optical splitters, directional couplers. Furthermore, an optical transmission module in which laser diodes and photodiodes are integrated in a hybrid manner can be used.

  Next, examples will be described.

  First, prior to Examples, 2- (3-oxetanyl) butyl tosylate, which is a sulfonic acid ester of 3-alkyl-3-hydroxymethyloxetane, was synthesized as follows.

[Synthesis of 2- (3-oxetanyl) butyl tosylate]
In a 2000 ml three-necked eggplant flask equipped with a thermometer, a condenser, a stirrer and a dropping funnel, 190.65 g (1.0 mol) of p-toluenesulfonic acid chloride, 32.24 g (0.1 mol) of tetramethylammonium bromide and toluene 400 ml was added and cooled to 5 ° C. with stirring in an ice bath. After adding 116.16 g (1.0 mmol) of 3-ethyl-hydroxymethyloxetane to this, 130 ml of 35 wt% sodium hydroxide aqueous solution was dripped over 30 minutes with the dropping funnel. After completion of the dropwise addition, the mixture was stirred at the same temperature for 1 hour, and further stirred at room temperature for 16 hours. After completion of the reaction, 800 ml of water was added to the flask and stirred vigorously, and then left to separate into an aqueous phase and an organic phase. This organic phase was further washed with 400 ml of water and dried over anhydrous magnesium sulfate overnight. Then, magnesium sulfate was filtered and the filtrate was concentrated. The obtained crude product was separated and purified by silica gel column chromatography (eluent: hexane / ethyl acetate), and 243.3 g of 2- (3-oxetanyl) butyl tosylate as a colorless liquid as a target product (yield 90). %).

[Example 1]
In a 200 ml three-necked flask equipped with a thermometer, a condenser and a stirrer, 3.36 g (20 mmol) of methyl 3,5-dihydroxybenzoate and 20 ml of N-methyl-2-pyrrolidone were placed under a nitrogen atmosphere. Stir until completely dissolved while heating at ℃. After dissolution, 15.64 g (48 mmol) of cesium carbonate was added, and the mixture was further stirred at 80 ° C. for 30 minutes in a nitrogen atmosphere. Thereto was added 11.90 g (44 mmol) of 2- (3-oxetanyl) butyl tosylate synthesized earlier, and the mixture was stirred at 80 ° C. for 20 hours in a nitrogen atmosphere. After completion of the reaction, the reaction mixture was cooled to room temperature, and then 100 ml of ethyl acetate and 50 ml of distilled water were added to separate into an organic phase and an aqueous phase. The organic phase was further washed with water and saturated brine, and dried over anhydrous magnesium sulfate overnight. After magnesium sulfate was filtered off, the solvent was distilled off to obtain a crude product.

  The crude product thus obtained was analyzed by thin layer chromatography, and only one spot was confirmed. This was purified by recrystallization to obtain 6.01 g (yield 82%) of a white solid. Subsequently, this methyl ester was hydrolyzed.

  In a 100 ml flask, 3.00 g (8.2 mmol) of the obtained white solid, 20 ml of dehydrated methanol, and 0.99 g (24.7 mmol) of sodium hydroxide were placed, and stirred at 30 ° C. for 4 hours under a nitrogen atmosphere. After completion of the reaction, 1N hydrochloric acid and distilled water were added while cooling, and the precipitated solid was separated by filtration. The solid was further washed with distilled water and ethyl acetate and dried to obtain 2.72 g (yield 94%) of a white solid. When the purity of this compound was examined by liquid chromatography, it was 99% or more.

The compound obtained as described above is a bisoxetane having a carboxyl group represented by the following structural formula (9) as a result of ¹ H-NMR and ¹³ C-NMR (both manufactured by JEOL Ltd.) shown below. It was confirmed to be an ether compound.

¹ H-NMR (DMSO-d ₆ , 400 MHz): δ (ppm); 0.89 (t, J = 7.6 Hz, 6H, CH ₃ ), 1.78 (q, J = 7.6 Hz, 4H, CH ₂ ), 4.13 (s, 4H, CH ₂ ), 4.33 (d, J = 6.4 Hz, 4H, CH ₂ ), 4.45 (d, J = 5.6 Hz, 4H, CH ₂ ), 6.87 (t, J = 2.4 Hz, 1H, Ar), 7.13 (d, J = 2.4 Hz, 2H, Ar), 13.02 (br, s, 1H, COOH)
¹³ C-NMR (DMSO-d ₆ , 100 MHz): δ (ppm); 8.00, 26.18, 42.43, 70.49, 76.71, 105.80, 107.86, 132.87, 159. 89, 166. 86

[Example 2]
In a 200 ml three-necked flask equipped with a thermometer, a condenser and a stirrer, 4.20 g (20 mmol) of dimethyl 5-hydroxyisophthalate and 20 ml of N-methyl-2-pyrrolidone were placed at 80 ° C. in a nitrogen atmosphere. Stir while heating until completely dissolved. After dissolution, 7.82 g (24 mmol) of cesium carbonate was added, and the mixture was further stirred at 80 ° C. for 30 minutes in a nitrogen atmosphere. Thereto was added 5.94 g (22 mmol) of 2- (3-oxetanyl) butyl tosylate synthesized earlier, and the mixture was stirred at 80 ° C. for 20 hours in a nitrogen atmosphere. After completion of the reaction, the reaction mixture was cooled to room temperature, and then 100 ml of ethyl acetate and 50 ml of distilled water were added to separate into an organic phase and an aqueous phase. The organic phase was further washed with distilled water and saturated brine, and dried over anhydrous magnesium sulfate overnight. After magnesium sulfate was filtered off, the solvent was distilled off to obtain a crude product.

  The crude product thus obtained was analyzed by thin layer chromatography, and only one spot was confirmed. This was purified by silica gel chromatography (eluent: n-hexane / ethyl acetate) to obtain 5.32 g (yield 86%) of a white solid. Subsequently, the dimethyl ester was hydrolyzed.

  5.00 g (16 mmol) of the obtained white solid, 10 ml of dehydrated methanol, and 3.71 g (66 mmol) of potassium hydroxide were placed in a 100 ml capacity flask and stirred at 30 ° C. for 20 hours under a nitrogen atmosphere. After completion of the reaction, the reaction mixture was acidified with 1N hydrochloric acid while cooling. 200 ml of ethyl acetate and 100 ml of distilled water were added to separate into an organic phase and an aqueous phase. The organic phase was further washed with water and saturated brine, and dried over anhydrous magnesium sulfate overnight. After magnesium sulfate was filtered off, the solvent was distilled off to obtain 3.37 g (yield 70%) of a white solid. When the purity of this compound was examined by liquid chromatography, it was 99% or more.

The compound obtained as described above is a monooxetane having a carboxyl group represented by the following structural formula (10) as a result of ¹ H-NMR and ¹³ C-NMR (both manufactured by JEOL Ltd.) shown below. It was confirmed to be an ether compound.

¹ H-NMR (DMSO-d ₆ , 400 MHz): δ (ppm); 0.90 (t, J = 7.6 Hz, 3H, CH ₃ ), 1.80 (q, J = 7.6 Hz, 2H, _{CH 2), 4.21 (s,} 2H, CH 2), 4.34 (d, J = 5.6Hz, 2H, CH 2), 4.47 (d, J = 6.0Hz, 2H, CH 2 ), 7.70 (d, J = 1.6 Hz, 2H, Ar), 8.09 (s, 1H, Ar), 13.29 (br, s, 2H, COOH)
¹³ C-NMR (DMSO-d ₆ , 100 MHz): δ (ppm); 8.04, 26.22, 42.47, 70.75, 76.68, 119.21, 122.48, 132.66, 158. 90, 166. 38

Example 3
In the following manner, an under cladding layer, a core portion, and an under cladding layer were formed to produce an optical waveguide (see FIG. 1). And the evaluation with respect to the optical waveguide was performed as follows.

[Formation of underclad layer]
First, 70 parts by weight (hereinafter abbreviated as “part”) of the monooxetane ether compound having a carboxyl group obtained in Example 1 and 3,4-epoxycyclohexenylmethyl-3 ′, 4 ′ which is an alicyclic epoxy. -Epoxycyclohexene carboxylate (Daicel Chemical Industries, Celoxide 2021P) 30 parts and 4,4-bis [di (βhydroxyethoxy) phenylsulfinio] phenyl sulfide-bis-hexafluoroantimonate 50% propion carbide 1 part of the solution was dissolved in cyclohexanone to prepare a polymerizable composition A for forming a clad layer. Next, an Si substrate (5 cm × 5 cm × thickness 2 mm) was prepared, and the polymerizable composition A was applied to the surface by a spin coating method and dried at 100 ° C. for 5 minutes. Then, the entire surface was irradiated with ultraviolet rays at a dose of 2000 mJ / cm ² , and subsequently heat-treated at 100 ° C. for 30 minutes to form an under cladding layer (see FIG. 2B). It was 30 micrometers when the thickness of this under clad layer was measured with the contact-type film thickness meter. The refractive index of the underclad was 1.491 at a wavelength of 633 nm.

[Formation of core part]
90 parts of a monooxetane ether compound having a carboxyl group obtained in Example 1, 10 parts of bisphenoxyethanol fluorenediglycidyl ether (epoxy equivalent 320), 4,4-bis [di (βhydroxyethoxy) phenylsulfinio ] 1 part of 50% propion carbide solution of phenyl sulfide-bis-hexafluoroantimonate was dissolved in cyclohexanone to prepare a polymerizable composition B for forming a core part. And the said polymeric composition B was apply | coated on the said under clad layer by the spin coat method (refer FIG.2 (c)). Then, this coated layer was dried at 150 ° C. for 20 minutes, and a synthetic quartz-based chromium mask (photomask) on which a 50 μm-wide linear optical waveguide pattern was drawn was further disposed (FIG. 2 (d) )), And an ultraviolet ray with an irradiation amount of 2000 mJ / cm ² was irradiated through this chrome mask by a contact exposure method, and further a heat treatment was performed at 150 ° C. for 30 minutes. Then, in order to remove an unirradiated part, development was performed using a γ-butyrolactone aqueous solution, and the core pattern was formed by further heating at 150 ° C. for 30 minutes (see FIG. 2E). When the core shape was measured with a length measuring microscope, the core pattern had a square cross-sectional shape with a width of 50 μm and a height of 50 μm. Further, the refractive index of the core portion formed in this way was 1.518 at a wavelength of 633 nm.

[Formation of overclad layer]
The same composition as the polymerizable composition A prepared at the time of forming the underclad layer was applied onto the core part and the underclad layer by a spin coating method. Next, it was dried at 100 ° C. for 5 minutes, irradiated with ultraviolet rays at an irradiation amount of 2000 mJ / cm ² , and subsequently heat-treated at 150 ° C. for 60 minutes to form an overcladding layer (FIG. 2 ( f)). In this way, an optical waveguide having a relative refractive index Δ = 1.8% was produced.

[Evaluation]
The optical waveguide was cut into a length of 10 cm using a dicing apparatus (Model 522 manufactured by Disco Corporation) and subjected to end face processing. When the cross-sectional shape of the optical waveguide was observed with a length measuring microscope, it was found to be a buried multimode optical waveguide with an under cladding layer thickness of 30 μm, a core portion of 50 μm × 50 μm, and an over cladding layer thickness of 70 μm. It was confirmed. And when this optical waveguide was measured for light propagation loss by a conventional cutback method using laser light having a wavelength of 850 nm, it was 0.09 dB / cm.

Example 4
In the following manner, an under cladding layer, a core portion, and an under cladding layer were formed to produce an optical waveguide (see FIG. 1). And the evaluation with respect to the optical waveguide was performed as follows.

[Formation of underclad layer]
First, 70 parts of the bisoxetane ether compound having a carboxyl group obtained in Example 2 and 3,4-epoxycyclohexenylmethyl-3 ', 4'-epoxycyclohexene carboxylate (Daicel Chemical Industries), which is an alicyclic epoxy, are used. 30 parts of Celoxide 2021P) and 1 part of 50% propion carbide solution of 4,4-bis [di (βhydroxyethoxy) phenylsulfinio] phenyl sulfide-bis-hexafluoroantimonate dissolved in cyclohexanone Then, a polymerizable composition C for forming a cladding layer was prepared. Next, an Si substrate (5 cm × 5 cm × thickness 2 mm) was prepared, and the polymerizable composition C was applied to the surface by a spin coating method and dried at 100 ° C. for 5 minutes. Then, the entire surface was irradiated with ultraviolet rays at a dose of 2000 mJ / cm ² , and subsequently heat-treated at 100 ° C. for 30 minutes to form an under cladding layer (see FIG. 2B). It was 30 micrometers when the thickness of this under clad layer was measured with the contact-type film thickness meter. The refractive index of the underclad was 1.487 at a wavelength of 633 nm.

[Formation of core part]
90 parts of the bisoxetane ether compound having a carboxyl group obtained in Example 2, 10 parts of bisphenoxyethanol fluorenediglycidyl ether (epoxy equivalent 320), 4,4-bis [di (β-hydroxyethoxy) phenylsulfinio A 1 part 50% propion carbide solution of phenyl sulfide-bis-hexafluoroantimonate was dissolved in cyclohexanone to prepare a polymerizable composition D for forming a core part. And the said polymeric composition D was apply | coated on the said under clad layer by the spin coat method (refer FIG.2 (c)). Then, this coated layer was dried at 150 ° C. for 20 minutes, and a synthetic quartz-based chromium mask (photomask) on which a 50 μm-wide linear optical waveguide pattern was drawn was further disposed (FIG. 2 (d) )), And an ultraviolet ray with an irradiation amount of 2000 mJ / cm ² was irradiated through this chrome mask by a contact exposure method, and further a heat treatment was performed at 150 ° C. for 30 minutes. Then, in order to remove an unirradiated part, development was performed using a γ-butyrolactone aqueous solution, and the core pattern was formed by further heating at 150 ° C. for 30 minutes (see FIG. 2E). When the core shape was measured with a length measuring microscope, the core pattern had a square cross-sectional shape with a width of 50 μm and a height of 50 μm. Further, the refractive index of the core portion formed in this way was 1.516 at a wavelength of 633 nm.

[Formation of overclad layer]
The same polymerizable composition C prepared during the formation of the underclad layer was applied onto the core part and the underclad layer by a spin coating method. Next, it was dried at 100 ° C. for 5 minutes, irradiated with ultraviolet rays at an irradiation amount of 2000 mJ / cm ² , and subsequently heat-treated at 150 ° C. for 60 minutes to form an overcladding layer (FIG. 2 ( f)). In this manner, an optical waveguide having a relative refractive index Δ = 1.9% was produced.

[Evaluation]
The optical waveguide was cut into a length of 10 cm using a dicing apparatus (Model 522 manufactured by Disco Corporation) and subjected to end face processing. When the cross-sectional shape of the optical waveguide was observed with a length measuring microscope, it was found to be a buried multimode optical waveguide with an under cladding layer thickness of 30 μm, a core portion of 50 μm × 50 μm, and an over cladding layer thickness of 70 μm. It was confirmed. Then, the optical propagation loss of this optical waveguide was measured by a conventional cutback method using a laser beam having a wavelength of 850 nm, and found to be 0.08 dB / cm.

  The oxetane ether compound having a carboxyl group of the present invention is used as a constituent of a photocurable resin composition or a thermosetting resin composition, and these resin compositions include, for example, paints, coating materials, adhesives, and optical lenses. It is used for various forming materials such as optical waveguides. Examples of the optical waveguide include a straight optical waveguide, a curved optical waveguide, a crossed optical waveguide, a Y-branch optical waveguide, a slab optical waveguide, a Mach-Zehnder optical waveguide, an AWG optical waveguide, a grating, and an optical waveguide lens. It is done. The optical device using the optical waveguide includes a wavelength filter, an optical switch, an optical splitter, an optical multiplexer, an optical multiplexer / demultiplexer, an optical amplifier, a wavelength converter, a wavelength divider, an optical splitter, and directional coupling. And an optical transmission module in which a laser diode and a photodiode are hybrid-integrated.

It is a cross-sectional view showing an example of the optical waveguide of the present invention. It is explanatory drawing which shows the manufacturing process of the optical waveguide of this invention.

Explanation of symbols

1 Substrate 2 Clad layer 3 Core part

Claims (5)

An oxetane ether compound having a carboxyl group represented by the following general formula (1) or general formula (2).
It is a manufacturing method of the oxetane ether compound which has a carboxyl group of Claim 1, Comprising: The phenol represented by following General formula (3) or General formula (4) is cesium phenolate by a cesium salt, Then, The manufacturing method of the oxetane ether compound which has a carboxyl group characterized by making it react with the sulfonic acid ester represented by General formula (5).
  The method for producing an oxetane ether compound having a carboxyl group according to claim 2, wherein the cesium salt is cesium carbonate.   An optical waveguide comprising a substrate and a clad layer formed on the substrate, wherein a core portion that propagates an optical signal in a predetermined pattern is formed in the clad layer, wherein the clad layer and the core portion At least one is formed with the resin composition containing the oxetane ether compound which has a carboxyl group of Claim 1, The optical waveguide characterized by the above-mentioned.   The at least one of the said cladding layer and core part is formed of the resin composition containing the oxetane ether compound which has the carboxyl group of Claim 1, and the compound which has an epoxy group or a vinyl ether group. Optical waveguide.